Communication method and apparatus in wireless communication system

ABSTRACT

Methods and devices in a wireless communication system are provided. A method includes receiving, from a base station, a radio resource control (RRC) reconfiguration message configuring a medium access control (MAC) parameter for the terminal, identifying an uplink grant for a MAC protocol data unit (PDU); identifying that skip uplink transmission information indicating for the terminal to skip an uplink transmission is configured in the RRC reconfiguration message and that the uplink grant is addressed to a cell-radio network temporary identifier (C-RNTI) or is a configured uplink grant; and skipping a generation of the MAC PDU for the uplink grant, in case that a MAC service data unit (SDU) for the MAC PDU does not exist, and the MAC PDU includes only a padding buffer status report (BSR).

PRIORITY

This application is a Continuation Application of U.S. Application No.17/410,484, filed in the U.S. Pat. and Trademark Office (USPTO) on Aug.24, 2021, which is a Continuation Application of U.S. Application No.16/588,382, filed in the USPTO on Sep. 30, 2019, now U.S. Pat. No.11,109,254, issued on Aug. 31, 2021, which is a Continuation of U.S.Application No. 15/744,677, which was filed in the USPTO on Jan. 12,2018, now U.S. Pat. No. 10,582,403, issued on Mar. 3, 2020, which is aNational Phase Entry of PCT International Application No.PCT/KR2016/007759, which was filed on Jul. 15, 2016, and claims priorityto U.S. Provisional Application Nos. 62/194,632, 62/197,383, and62/316,056, which were filed in the USPTO on Jul. 20, 2015, Jul. 27,2015, and Mar. 31, 2016, respectively, the content of each of which isincorporated herein by reference.

BACKGROUND 1. Field

The present invention relates to a method and apparatus for wirelesscommunication in a wireless communication system.

2. Art

Wireless communication systems that were providing voice-based serviceshave evolved to broadband wireless communication systems that arecapable of providing packet data services based on high quality and highspeed, such as: Long Term Evolution (LTE) or Evolved UniversalTerrestrial Radio Access (E-UTRA), LTE-Advanced (LTE-A) or EUTRAEvolution, High Speed Packet Access (HSPA) defined in 3GPP; Ultra MobileBroadband (UMB), High Rate Packet Data (HRPD) defined 3GPP2; thecommunication standard IEEE 802.16e; etc. LTE-A refers to systemsevolved from LTE. LTE-A further includes functions such as CarrierAggregation (CA), Higher order Multiple Input Multiple Output (Higherorder MIMO), etc. in addition to functions of LTE. In the followingdescription, the terms LTE and LTE-A will be used in the same sense aslong as they are not specifically indicated.

The LTE and LTE-A systems, as typical examples of the broadband wirelesscommunication systems, employ Orthogonal Frequency Division Multiplexing(OFDM) in the downlink and Single Carrier-Frequency Division MultipleAccess (SC-FDMA) in the uplink. The Multiple Access performs allocationand management of time-frequency resources to carry data and controlinformation according to users, so as not to overlap each other, i.e.,so as to achieve orthogonality between them, thereby distinguishing dataor control information between respective users.

In order to meet the increase in the demand for wireless data trafficafter the commercialization of 4G communication systems, considerableeffort has been made to develop pre-5G communication systems or improved5G communication systems. This is one reason why ‘5G communicationsystems’ or ‘pre-5G communication systems’ are called ‘beyond 4G networkcommunication systems’ or ‘post LTE systems.’ In order to achieve a highdata transmission rate, 5G communication systems are being developed tobe implemented in a band of extremely high frequency, or millimeter wave(mmWave), e.g., a band of 60 GHz. In order to reduce the occurrence ofstray electric waves in a band of extremely high frequency energy and toincrease the transmission distance of electric waves in 5G communicationsystems, various technologies being explored, for example: beamforming,massive MIMO, Full Dimensional MIMO (FD-MIMO), array antennas, analogbeam-forming, large scale antennas, etc. In order to improve systemnetworks for 5G communication systems, various technologies have beendeveloped, e.g., evolved small cell, advanced small cell, cloud radioaccess network (cloud RAN), ultra-dense network, Device to Devicecommunication (D2D), wireless backhaul, moving network, cooperativecommunication, Coordinated Multi-Points (CoMP), interferencecancellation, etc. In addition, for 5G communication systems, othertechnologies have been developed, e.g., Hybrid FSK and QAM Modulation(FQAM) and Sliding Window Superposition Coding (SWSC), as AdvancedCoding Modulation (ACM), Filter Bank Multi Carrier (FBMC),non-orthogonal multiple access (NOMA), sparse code multiple access(SCMA), etc.

The Internet has evolved from a human-based connection network, wherehumans create and consume information to the Internet of Things (IoT)where distributed configurations, such as objects, exchange informationwith each other to process the information. The technology related tothe IoT is starting to be combined with, for example, a technology forprocessing big data through connection with a cloud server, and this iscalled an Internet of Everything (IoE) technology. In order to manifestthe IoT, various technical components are required, such as, a sensingtechnology, wired/wireless communication and network infra technology, aservice interfacing technology, a security technology, etc. In recentyears, a sensor network for connecting objects, Machine to Machine(M2M), Machine Type Communication (MTC), etc. have been researched.Under the IoT environment, intelligent Internet Technology (IT) servicesmay be provided to collect and analyze data obtained from objectsconnected to each other and thus to create new value for human life. Asexisting information technologies are fused and combined with variousindustries, the IoT may also be applied within various fields, such as:smart homes, smart buildings, smart cities, smart cars or connectedcars, smart grids, health care, smart home appliances, high qualitymedical services, etc.

Various attempts have been made to apply 5G communication systems to theIoT network. For example, various technologies related to sensornetworks, Machine to Machine (M2M), Machine Type Communication (MTC),etc., have been implemented by beam-forming, MIMO, array antenna, etc.,as 5G communication technology. The application of the cloud RAN as abig data processing technology described above may be an example of ahybrid of 5G technology and IoT technology. Wireless communicationsystems have evolved in software or hardware to provide higher qualitycommunication. For example, a communication technology has beendeveloped to employ a number of antennas. A technology for efficientlyrestoring data from physical signals has made progress.

In order to meet the increasing demand in large communication capacity,a number of technologies have been proposed, e.g., a method of providinga number of connections. In Long Term Evolution (LTE) systems, a carrieraggregation (CA) technique provides a number of connections using anumber of carriers, so that users can receive various services via anumber of resources.

The present invention has been made to address the above problems anddisadvantages, and to provide at least the advantages described below.Various embodiments of the present invention provide a method andapparatus for providing dual connectivity using radio accesstechnologies (RATs) that differ from each other in a wirelesscommunication system.

SUMMARY

In accordance with an aspect of the present invention, a methodperformed by a terminal in a wireless communication system is provided.The method includes method performed by a terminal in a wirelesscommunication system, the method comprising: receiving, from a basestation, a radio resource control (RRC) reconfiguration messageconfiguring a medium access control (MAC) parameter for the terminal;identifying an uplink grant for a MAC protocol data unit (PDU);identifying that skip uplink transmission information indicating for theterminal to skip an uplink transmission is configured in the RRCreconfiguration message and that the uplink grant is addressed to acell-radio network temporary identifier (C-RNTI) or is a configureduplink grant; and skipping a generation of the MAC PDU for the uplinkgrant, in case that a MAC service data unit (SDU) for the MAC PDU doesnot exist, and the MAC PDU includes only a padding buffer status report(BSR).

In accordance with another aspect of the present invention, a methodperformed by base station in a wireless communication system isprovided. The method includes transmitting, to a terminal, an RRCreconfiguration message configuring a MAC parameter for the terminal;and allocating an uplink grant for a MAC PDU. A generation of the MACPDU is skipped for the uplink grant, in case that: skip uplinktransmission information indicating for the terminal to skip an uplinktransmission is configured in the RRC reconfiguration message and theuplink grant is addressed to a C-RNTI or is a configured uplink grant,and a MAC SDU for the MAC PDU does not exist, and the MAC PDU includesonly a padding BSR.

In accordance with another aspect of the present invention, a terminalin a wireless communication system is provided. The terminal includes atransceiver; and a controller configured to receive, from a basestation, an RRC reconfiguration message configuring a MAC parameter forthe terminal, identify an uplink grant for a MAC PDU, identify that skipuplink transmission information indicating for the terminal to skip anuplink transmission is configured in the RRC reconfiguration message andthat the uplink grant is addressed to a C-RNTI or is a configured uplinkgrant, and skip a generation of the MAC PDU for the uplink grant, incase that a MAC SDU for the MAC PDU does not exist, and the MAC PDUincludes only a padding BSR.

In accordance with another aspect of the present invention, a basestation in a wireless communication system is provided. The base stationincludes a transceiver; and a controller configured to transmit, to aterminal, an RRC reconfiguration message configuring a MAC parameter forthe terminal, and allocate an uplink grant for a MAC PDU. A generationof the MAC PDU is skipped for the uplink grant, in case that: skipuplink transmission information indicating for the terminal to skip anuplink transmission is configured in the RRC reconfiguration message andthe uplink grant is addressed to a C-RNTI or is a configured uplinkgrant, and a MAC SDU for the MAC PDU does not exist, and the MAC PDUincludes only a padding buffer BSR.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the inventionwill be more apparent from the following detailed description, taken inconjunction with the accompanying drawings, in which:

FIG. 1 is a diagram showing the network configuration of a wirelesscommunication system according to Embodiment 1 of the present invention;

FIG. 2 is a diagram of a radio protocol stack in an LTE system accordingto the present invention;

FIG. 3 is a flow diagram showing the flow of messages between UE and eNBusing a measurement object indicator for a WLAN according to Embodiment1 of the present invention;

FIG. 4 is a flow diagram that describes a method for UE to calculate ameasurement object frequency when the UE receives a measurement objectindicator for a WLAN according to Embodiment 1 of the present invention;

FIG. 5 is a block diagram showing the configuration of UE in a wirelesscommunication system according to Embodiment 1 of the present invention;

FIG. 6 is a block diagram showing an ENB in a wireless communicationsystem according to Embodiment 1 of the present invention;

FIG. 7 is a diagram of a configuration of an LTE system according to thepresent invention;

FIG. 8 is a diagram of a radio protocol stack in an LTE system accordingto the present invention,

FIG. 9 is a flow diagram that describes the operations between UE andENB according to Embodiment 2-1;

FIG. 10 is a flowchart that describes operations of UE according toEmbodiment 2-1;

FIG. 11 is a flow diagram that describes the operations between UE andENB according to Embodiment 2-2;

FIG. 12 is a flowchart that describes operations of UE according toEmbodiment 2-2;

FIG. 13 is a flow diagram that describes the operations between UE andENB according to Embodiment 2-3;

FIG. 14 is a flowchart that describes operations of UE according toEmbodiment 2-3;

FIG. 15 is a block diagram showing of the configuration of UE in awireless communication system according to Embodiment 2;

FIG. 16 is a block diagram showing the configuration of an ENB in awireless communication system according to Embodiment 2;

FIG. 17 is a diagram for explaining the enhanced carrier aggregation ofa UE;

FIG. 18 is a diagram for explaining PUCCH SCell activation in accordancewith the normal SCell activation procedure;

FIG. 19 shows a legacy Activation/Deactivation MAC Control Element (A/DMAC CE) format;

FIG. 20 is a diagram illustrating an extended A/D MAC CE for supportingup to 32 serving cells;

FIG. 21 is a signal flow diagram illustrating a method of selecting oneof the legacy and extended A/D MAC CEs according to the presentinvention;

FIG. 22 is a flowchart illustrating an eNB operation according to thepresent invention;

FIG. 23 is a flowchart illustrating a UE operation according to thepresent invention;

FIG. 24 is a block diagram illustrating a UE according to the presentinvention; and

FIGS. 25A, 25B, and 25C illustrate example bit maps according to thepresent invention.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention are described indetail with reference to the accompanying drawings. The same referencenumbers are used throughout the drawings to refer to the same or similarparts. Detailed descriptions of well-known functions and structuresincorporated herein may be omitted to avoid obscuring the subject matterof the invention.

In the following description, part of the embodiments of the presentinvention will be described based on Advanced E-UTRA (also called LTE-A)supporting carrier aggregation; however, it will be appreciated to thoseskilled in the art that the subject matter of the present invention canalso be applied to various types of communication systems which have thetechnical background and channel forms similar to those of the presentinvention, without departing from the scope and sprit of the presentinvention. For example, the subject matter of the present invention maybe applied to multicarrier HSPA supporting carrier aggregation.

In the following description, certain detailed explanations of relatedart are omitted when it is deemed that they may unnecessarily obscurethe essence of the invention.

Although the drawings represent embodiments of the present invention,they are not necessarily to scale and certain features may beexaggerated or omitted in order to better illustrate and explain thepresent invention. The same reference numbers are used throughout thedrawings to refer to the same or similar parts.

The features and advantages of the present invention and the method toachieve them will become more apparent from the following detaileddescription in conjunction with the accompanying drawings. It will beeasily appreciated to those skilled in the art that variousmodifications, additions and substitutions are possible from theembodiments of the invention that are illustrated and described indetail in the following description, and the scope of the inventionshould not be limited to the following embodiments. The embodiments ofthe present invention are provided such that those skilled in the artcompletely understand the invention. It should be understood that theinvention may include all modifications and/or equivalents and/orsubstations included in the idea and technical scope of the presentdisclosure. In the drawings, the same or similar elements are denoted bythe same reference numbers even though they are depicted in differentdrawings.

In addition, it should be understood that the processes, operations ofthe flow diagrams and a combination thereof can be performed viacomputer programming instructions. These computer programminginstructions can be installed to processors of data processing equipmentthat can be programmed, special computers, or universal computers. Theinstructions, performed via the processors of data processing equipmentor the computers, can generate means that perform functions described inblocks of the flow diagram. In order to implement functions in aparticular mode, the computer programming instructions can also bestored in a computer available memory or computer readable memory thatcan support computers or data processing equipment that can beprogrammed. Therefore, the instructions, stored in the computeravailable memory or computer readable memory, can be installed to theproducts, and perform the functions therein, described in the blocks ofthe flow diagram therein. In addition, since the computer programminginstructions can also be installed to computers or data processingequipment that can be programmed, they can create processes that performa series of operations therein, described in the blocks of the flowdiagram therein.

The blocks of the flow diagram refer to part of codes, segments ormodules that include one or more executable instructions to perform oneor more logic functions. It should be noted that the functions describedin the blocks of the flow diagram may be performed in a different orderfrom the embodiments described above. For example, the functionsdescribed in two adjacent blocks may be performed at the same time or inreverse order.

In the embodiments, the terminology ‘~ unit’ representing a componentrefers to a software element or a hardware element such as a PGGA, anASIC, etc., and performs a corresponding function. It should be,however, understood that the component ‘~unit’ is not limited to asoftware or hardware element. The component ‘~unit’ may be implementedin storage media that can be designated by addresses. The component‘~unit’ may also be configured to regenerate one or more processors. Forexample, the component ‘~unit’ may include various types of elements(e.g., software elements, object-oriented software elements, classelements, task elements, etc.), segments (e.g., processes, functions,achieves, attribute, procedures, sub-routines, program codes, etc.),drivers, firmware, micro-codes, circuit, data, data base, datastructures, tables, arrays, variables, etc. Functions provided byelements and the components ‘~units’ may be formed by combining thesmall number of elements and components ‘~units’ or may be divided intoadditional elements and components ‘~units.’ In addition, elements andcomponents ‘~units’ may also be implemented to regenerate one or moreCPUs in devices or security multi-cards.

Embodiment 1

Embodiment 1 relates to a technology for providing dual connectivity toa wireless communication system.

In the following description, terms used to identify an access node,terms referred to as network entities, terms expressing messages, termsrepresenting interfaces between network objects, terms used for varioustypes of identification information, etc. are used for the sake ofconvenient description. Therefore, the present invention is not limitedby the terms and may use other terms with the meanings equivalent to theterms described in the present disclosure, representing thecorresponding components.

For the sake of convenient description, the present disclosure usesterms and names defined in the specifications of the 3rd GenerationPartnership Project Long Term Evolution (3GPP LTE) and Institute ofElectrical and Electronic Engineers (IEEE) 802.11. However, it should beunderstood that the present invention is not limited to the terms andnames and may also be applied to systems following the other standards.

The following description explains embodiments of the present inventionthat provide the dual connectivity using a wireless local area network(WLAN) technology in cellular communication systems. However, it shouldbe understood that the present invention may also be applied to a radioaccess technology (RAT).

FIG. 1 is a diagram showing the network configuration of a wirelesscommunication system according to an embodiment of the presentinvention.

With reference to FIG. 1 , the wireless communication system includeseNB A(110-1), eNB B(110-2), eNB C(110-3), mobility management entities(MMEs)/serving-gateways (S-GWs) 1 1/1-0-1 and 120-2, and access point(AP) 150. Although the embodiment is described based on three eNBs, itshould be understood that the embodiment may also be modified in such away as to include two eNBs or four or more eNBs. The MMEs/S-GWs 120-1and 120-2 may be separated into MMEs and S-GWs.

The eNBs 110-1, 110-2, and 110-3) are referred to as access nodes of acellular network and provide wireless access to UE devices to connect toa network. That is, the eNBs 110-1, 110-2, and 110-3 support connectionbetween the UE devices and a core network. According to variousembodiments of the present invention, the eNB A (110-1) provides the UEwith the dual connectivity via the AP 150.

The MMEs/S-GWs 120-1 and 120-2 manage the mobility of UE. The MMEs/S-GWs120-1 and 120-2 may also perform the authentication for UE to connect toa network, bearer management, etc. The MMEs/S-GWs 120-1 and 120-2process packets transmitted from the eNB 220 or packets to be forwardedto the eNBs 110-1 , 110-2, and 110-3.

The AP 150 is an access node of a WLAN and provides wireless access toUE devices. In particular, according to various embodiments of thepresent invention, the AP 150 is capable of providing UE with theWLAN-based connection for dual connectivity, according to the control ofthe eNB A (110-1). According to various embodiments of the presentinvention, the AP 150 may be included in the eNB A (110-1) or may beconnected to the eNB A (110-1) via a separate interface. In this case,the eNB A (110-1) is capable of transmitting: part of the downlink datato the UE; or the other data to the UE via the AP 150. The UE is capableof transmitting: part of the uplink data to the eNB A (110-1); and theother data to the AP 150.

UE is capable of connecting to a cellular network via the eNB A (110-1).According to an embodiment of the present invention, the eNB A (1 1 0-1)additionally sets the UE to connect to the AP 150, thereby enabling theUE to make a communication on a broader band. Although a core networkentity (e.g., MME, S-GW, packet data network gateway (P-GW), etc.) doesnot recognize that dual connectivity has been set by additionally usingthe All 150 in a wireless area, it may provide services. In this case,the dual connectivity is called LTE-WLAN aggregation (or earneraggregation (CA) or integration).

When the entity provides the dual connectivity via the AP 150, aconnection to transmit data needs to be determined. For example, in thecase of downlink, the eNB A (110-1) receives data from a core networkand determines whether it will transmit the data directly or via a WLAN.In the case of uplink, the UE determines a path to transmit data andtransmits the data to the core network.

FIG. 2 is a diagram of a radio protocol stack in an LTE system accordingto the present invention.

With reference to FIG. 2 , UE and ENB have Packet Data ConvergenceProtocol (PDCP) 205 and 240, Radio Link Control (RLC) 210 and 235, andMedium Access Control (MAC) 215 and 230, respectively. PDCP 205 and 240compress/decompress the IP header. RLC 210 and 235 reconfigure PDCPpacket data unit (PDU) in proper size. MAC 215 and 230 connect to anumber of RLC layer devices configured in one UE device. MAC 215 and 230multiplex RLC PUDs to MAC PDU, and de-multiplex RLC PDUs from MAC PDU.Physical layers (PHY) 220 and 225 in UE and eNB channel-code andmodulate data from the higher layers, create OFDM symbols, and transmitthem via a wireless channel In addition, PHY 220 and 225 demodulate andchannel-decode OFDM symbols received via a wireless channel, andtransfer them to the higher layers. In addition, the PHY uses Hybrid ARQ(HARQ) to perform additional error correction. The receiver transmits,to the transmitter, a 1-bit signal for a condition as to whether it hasreceived a packet transmitted from the transmitter, which is called HARQACK/NACK information. Downlink HARQ ACK/NACK information in response tothe uplink transmission is transmitted via a physical channel, PhysicalHybrid-ARQ Indicator Channel (PHICH). Uplink HARQ ACK/NACK informationin response to the downlink transmission is transmitted via a physicalchannel, Physical Uplink Control Channel (PUCCH) or Physical UplinkShared Channel (PUSCH).

FIG. 3 is a flow diagram showing the flow of messages between UE and eNBusing a measurement object indicator for a WLAN according to the presentinvention.

In the embodiment, it is assumed that UE 301 is connected to the LTE eNB303 (RRC __CONNECTED). In this case, UE and eNB may transmit/receivedata to/from each other.

The eNB 303 is capable of transmitting a message instructing to measurenearby WLANs to the UE 301 in order to configure the interworkingoperation or the integration/aggregation between LTE and WLAN inoperation 311. The measurement instruction message may containmeasurement object information and report configuration informationregarding a time and a form to report a corresponding measurementobject. The details of the measurement object may contain a WLAN APidentifier (e.g., SSII), BSSID, etc.) and/or a WLAN frequency. In theembodiment, the eNB is capable of instructing the UE to measure a WLANfrequency by combining the following.

-   Country-   Operating Class-   Channel number

The IEEE 802.11 specification as a WLAN standard defines operating classand a channel set of channel numbers in the operating class according tocountries. In the case of the US, part of the operating class is definedas in the following Table 1.

TABLE 1 Operati ng class Global Operatin g class (see Table E-4) Channelstarting frequenc y (GHz) Channe l spacing (MHz) Channel set Behaviorlimits set 1 115 5 20 36, 40, 44, 48 2 118 5 20 52, 56, 60, 64DFS_50_100_Behavior 3 124 5 20 149, 153, 157, 161 Nom adicB ehavi or 4121 5 20 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140DFS_50_100_Behavior 5 125 5 20 149, 153, 157, 161, 165LicenseExemptBehavior 6 103 4.9375 5 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 7 1034.9375 5 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 8 102 4.89 10 11, 13, 15, 17, 199 102 4.89 10 11, 13, 15, 17, 19 10 101 4.85 20 21, 25 11 101 4.85 2021, 25 12 81 2.407 25 1, 2, 3, 4, 5, 6, 7, 8, 9, 1 0, 11LicenseExemptBehavior 13 94 3.000 20 133, 133, 137 CCA-EDBehavior 14 1595 96 3.000 3.0025 10 5 132, 134, 136, 138 131, 132, 133, 134, 135, 136,137, 138 CCA-EDBehavior CCA-EDBehavior 16a 5.0025 5 170-184ITS_nonmobile operations, ITS_mobile_ operations 17^(a,) ^(b) 5 10171-184 ITS_nonmobile operations, ITS_mobile_ operations 18^(a,b) 5 2 0172-183 ITS_nonmobile operations, ITS_mobile_operations 19-21 ReservedReserved Reserve d Reserved Reserved 22 116 5 40 36, 44 PrimaryChannelLowerBeh avior 23 119 5 40 52, 60 Primary Channel LowerBeh avior24 122 5 40 100, 108, 116, 124, 132 Primary C hannelLowerB eh avior,DFS_50_100_Behavior 25 126 5 40 149, 157 PrimaryChannelLowerBeh avior 26126 5 40 149, 157 Li censeExemptBehavior, PrimaryChannelLowerBeh avior27 117 5 40 40, 48 Primary ChannelUpperBeha vior 28 120 5 40 56, 64PrimaryChannelUpperBeha vi or 29 123 5 40 104, 112, 120, 128, 136NomadicBehavior, PrimaryC hannelUpperBeha vior, DFS_50 _100 _Behavior

The WLAN channel frequency is calculated as in the following equation,referring to table 1.

Channel center frequency ::: Channel starting frequency + 5 × nch (MHz),where nch= 1, ..., 200.

In the case of {Country, Operating Class, Channel number = {US, 4, 120},this means that country is US and Operating Class is number 4.Therefore, referring to item number 4 of Operating Class in Table 1,Channel starting frequency is 5 GHz = 5000 MHz. In addition, since thechannel number is 120, the frequency of an actual channel is 5600 MHz (=5000 + 5 × 120).

When all the items, Country, Operating Class, and Channel number, areused, only one frequency may be indicated. When Country and OperatingClass are used, the UE is instructed to measure all Operating Classes inthe Channel Set. For example, when UE is signaled with the case of{Country, Operating Class, Channel number} = {US, 4, 120}, only afrequency of 5600 MHz may be indicated. When UE is signaled with thecase of {Country, Operating Class} = {US, 4}, it may be instructed tomeasure a total of 11 frequencies, i.e., 5500, 5520, . . . , 5700 MHz.

The individual fields. Country, Operating Class, and Channel number maybe signaled in the following methods.

-   Country    -   Alternative 1: 3 Octets (as a bit string; according to ISO/IEC        3166-1); or    -   Alternative 2: N bits or 1 Octet Integer-   Operating Class    -   1 Octet Integer-   Channel number    -   Alternative 1: List of Integer for each channel    -   Alternative 2: Variable-size bitmap according to the Operating        Class

For example, a field of country may be encoded with 3 bytes according tothe ISO/IEC 3166-1 specification defined as in the IEEE standard. Thatis, a country or non-country entity that UE/WLAN AP is running on may beidentified by 3 bytes. For the country entity, the first and secondoctets of the string correspond to two country codes described in theISO/IEC 3166-1 and the third octet corresponds to one of the following:

-   ASCII space character, (when regulations for the operations of    UE/WLAN AP include all the environments for the current frequency    band of the country);-   ASCII ‘O’ character, (when regulations for the operations of UE/WLAN    AP are related to outdoor environments),-   ASCII ‘I’ character, (when regulations for the operations of UE/WLAN    AP are related to indoor environments);-   ASCII ‘X’ character, (when UE/WLAN AP operates in a non-country    entity, the first and second octets of the non-country entity    correspond to two ASCII ‘XX’ characters); and-   Binary representation of a table number (refer to Table 1) of the    operating class in use.

In the current IEEE standard, the field of country is defined for onlyfour countries. Therefore, the country field may employ a format of twobits (representing four countries: 00, 01, 10, 11) or a format of 1byte-integer.

Alternatively, for the country field, when Mobile Country Code (MCC),contained in the Public Land Mobile Network Identity PLMN ID of an LTEeNB, is used, the transmission may be omitted. For example, in a statewhere System Information Block (SIB) that LTE eNB broadcasts to UE inthe coverage area carries MCC information in the PLMN and the MCCinformation is a value corresponding to the US (i.e., 310, 311, 312,313, 314, 315, 316), when UE is instructed to measure a WLAN frequencywithout the information regarding the country, it may calculate themeasured frequency assuming the country value is a value correspondingto the US. The MCC value is defined in the COMPLEMENT TO ITU-TRECOMMENDATION E.212 (11/98) of ITU-T.

Operating Class may employ a format of 1 byte-integer, for example.

The field of channel number may employ a format of a list of 1byte-integer for each channel. For example, the channel number of{Country, Operating Class} = {US, 4} may be indicated in the format of{100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140}. When the formatdescribed above is used and 11 channel numbers are employed, a resourceof 11 bytes is required. In order to reduce the bytes, a format ofbitmap according to Operating Class may be considered. For example, whenall channel numbers of {Country, Operating Class} = {US, 4} areindicated, since the channel number of {Country, Operating Class} = {US,4} is 11, it may be indicated using a bitmap of a length of 11 bits. Anexample of the bitmap is illustrated in FIG. 25A.

For example, when two channel numbers of {Country, Operating Class} ={US, 4}, i.e., {120, 140}, are indicated, since the channel number of{Country, Operating Class} = {US, 4} is 11, it may employ a bitmap of alength of 11 bits and may be indicated in such a way that the bit digitsto be indicated are set to ‘1’. An example of the bitmap is illustratedin FIG. 25B.

For example, when all channel numbers of {Country, Operating Class} ={US, 1} are indicated, since the channel number of {Country, OperatingClass} = {US, 1} is 4, it may be indicated using a bitmap of a length of4 bits, thereby instructing the UE to efficiently indicate themeasurement frequencies. An example of the bitmap is illustrated in FIG.25C.

When measurement frequencies are indicated using Country, OperatingClass, and Channel number, a frequency to be used for WLAN may bedefined in the future IEEE standard, using the Country, Operating Class,and Channel number values without change. Therefore, the method isadvantageous because it can instruct to measure frequencies to be usedfor WLAN defined in new IEEE standard without changing the specificationof the 3GPP standard.

The report configuration information, comprised in the measurementinstruction message transmitted in operation 311 of FIG. 3 , enables UEto report the measurement result of a measurement object, periodicallyor when a specified condition is satisfied. Examples of a specifiedcondition are as follows.

-   Event A1: Serving becomes better than absolute threshold.-   Event A2: Serving becomes worse than absolute threshold.-   Event A3: Neighbor becomes amount of offset better than PCell.-   Event A4: Neighbor becomes better than absolute threshold.-   Event A5: PCell becomes worse than absolute threshold1 AND Neighbor    becomes better than another absolute threshold2.-   Event A6: Neighbor becomes amount of offset better than SCell.

That is, when the level of signal strength/quality of a current LTE cellis greater or less than a threshold or the level of signalstrength/quality in a neighboring cell (or a WLAN) is greater or lessthan a threshold, UE may perform the reporting operation to the eNB. Themeasurement instruction message may be transmitted via a Radio ResourceControl (RRC) layer message, RRCConnectionReconfiguration. When UEreceives the RRCConnectionReconfiguration message in operation 311, ittransmits, to the eNB, the acknowledgement message notifying thesuccessful reception of the message, i.e., an RRC layer message, e.g.,RRCConnectionReconfigurationComplete, in operation 313.

The UE measures neighboring WLAN signals according to the instruction inoperation 315. The UE may use a beacon message transmitted from a WLANAP 305 to measure neighboring WLAN signals. When the UE has measuredsignals and ascertains that a report condition configured as inoperation 311 is satisfied, it reports the measurement result to the eNBin operation 321. The UE may use an RRC layer message to report themeasurement result, e.g., MeasurementReport.

When receiving the report message of the measurement result, the eNB iscapable of transmitting, to the UE, a message for instructing the UE toadditionally use or move to a WLAN, considering the reported signalstrength/quality, etc., so that the UE can perform the interworkingoperation or the integration/aggregation with the reported WLAN AP, inoperation 323. The instruction message may comprise an identifier of aWLAN as a destination, e.g., SSID, BSSID, etc. The instruction messagemay be transmitted via an RRC layer message,RRCConnectionReconfiguration. When the UE receives the message, ittransmits, to the eNB, the acknowledgement message notifying thesuccessful reception of the message, i.e., an RRC layer message, e.g.,RRCConnectionReconfigurationComplete, in operation 325.

FIG. 4 is a flow diagram that describes a method for UE to calculate ameasurement object frequency when the UE receives a measurement objectindicator for WLAN according to the present invention.

UE is capable of receiving, from the eNB, an RRC message for instructingthe measurement of a WLAN in operation 403. UE is capable of determiningwhether measurement object information representing a measurementfrequency, comprised in the measurement instruction message, includesinformation regarding a country in operation 405. When UE ascertainsthat measurement object information includes information regarding acountry in operation 405, it uses the included value of a country inoperation 407. On the other hand, when UE ascertains that measurementobject information does not include information regarding a country inoperation 405, it may calculate the value of a country by using MCCinformation comprised in a service provider’s identifier, PLMN ID, ofSIB that the LTE eNB broadcasts to UE in the coverage area in operation409. For example, in a state where MCC of the PLMN ID corresponds to avalue of the US (i.e., 310, 311, 312, 313, 316), when UE is instructedto measure a WLAN frequency without the information regarding a country,it may calculate the measurement frequency assuming the country value isa value corresponding to the US.

When the information regarding a country is determined as in operation407 or 409, the UE is capable of using Operating Class comprised in themeasurement object in operation 411.

When the measurement object information comprises information regardingan explicit channel number in operation 413, the UE is capable ofcalculating a measurement frequency for a channel number indicatedwithin operating class corresponding to the value of a country which isreceived or calculated in operation 415. The calculation of ameasurement frequency refers to the method described via the flow chartshown in FIG. 3 . When the measurement object information does notcomprise information regarding an explicit channel number, the UE iscapable of calculating measurement frequencies in all channel setswithin operating class corresponding to the value of a country which isreceived or calculated in operation 417. The UE is capable of performingthe measurement for the calculated frequency (frequencies) in operation421.

FIG. 5 is a block diagram showing the configuration of UE in a wirelesscommunication system according to an embodiment of the presentinvention.

With reference to FIG. 5 , the UE includes a Radio Frequency (RF)processing unit 510, a baseband processing unit 520, a storage unit 530,and a controller 540.

The RF processing unit 510 performs functions related to thetransmission/reception of signals via a wireless channel, e.g., theconversion of frequency band, the amplification, etc. The RF processingunit 510 up-converts baseband signals output from the basebandprocessing unit 520 into RF band signals and transmits the RF signalsvia an antenna. The RF processing unit 510 down-converts RF band signalsreceived via the antenna into baseband signals. The RF processing unit510 is capable of including a transmission filter, a reception filter,an amplifier, a mixer, an oscillator, a digital to analog convertor(DAC), an analog to digital convertor (ADC), etc. Although theembodiment is shown in FIG. 5 so that the UE includes only one antenna,it should be understood that the UE may be implemented to include anumber of antennas. The RF processing unit 510 may also be implementedto include a number of RF chains. The RF processing unit 510 is capableof performing a beamforming operation. In order to perform a beamformingfunction, the RF processing unit 510 is capable of adjusting the phaseand amplitude of individual signals transmitted/received via a number ofantennas or antenna elements.

The baseband processing unit 520 performs the conversion betweenbaseband signals and bitstream according to a physical layerspecification of the system. For example, in the transmission of data,the baseband processing unit 520 encodes and modulates a transmissionbitstream, thereby creating complex symbols. In the reception of data,the baseband processing unit 520 demodulates and decodes basebandsignals output from the RF processing unit 510, thereby restoring areception bitstream. For example, in the data transmission according tothe orthogonal frequency division multiplexing (OFDM), the basebandprocessing unit 520 encodes and modulates a transmission bitstream tocreate complex symbols, maps the complex symbols to sub-carriers, andconfigures OFDM symbols through the inverse fast Fourier transform(IFFT) operation and the cyclic prefix (CP) insertion. In the datareception, the baseband processing unit 520 splits baseband signalsoutput from the RF processing unit 510 into OFDM symbol units, restoressignals mapped to sub-carriers through the fast Fourier transform (FFT)operation, and then restores a reception bitstream through thedemodulation and the decoding operation.

The baseband processing unit 520 and the RF processing unit 510 performthe transmission and reception of signals as described above.Accordingly, the baseband processing unit 520 and the RF processing unit510 may also be called a transmitter, a receiver, a transceiver, acommunication unit, etc. In addition, the baseband processing unit 520and/or the RF processing unit 510 may include a number of communicationmodules to support wireless access technologies that differ from eachother. Alternatively, the baseband processing unit 520 and/or the RFprocessing unit 510 may include different communication modules toprocess signals of different frequency bands. Examples of the wirelessaccess technologies include wireless LAN (e.g., IEEE 802.11), a cellularnetwork (e.g., LTE), etc. Examples of the different frequency bandsinclude super high frequency (SHF) (e.g., 2.5 GHz band, 5 GHz band,etc.), millimeter wave (mmW) (e.g., 60 GHz band), etc.

The storage unit 530 stores a default program for operating the UE,applications, settings, data, etc. In particular, the storage unit 530is capable of storing information related to a second access node (e.g.,AP) which performs wireless communication using a second wireless accesstechnology (e.g., WLAN network). The storage unit 530 provides thestored data according to the request of the controller 540.

The controller 540 controls all operations of the UE. For example, thecontroller 540 controls the baseband processing unit 520 and the RFprocessing unit 510 to perform the transmission/reception of signals.The controller 540 controls the storage unit 530 to store/read datatherein/therefrom. To this end, the controller 540 is capable ofincluding at least one processor. For example, the controller 540 iscapable of including a communication processor (CP) for controlling thecommunication and an application processor (AP) for controlling higherlayers such as applications. According to embodiments of the presentinvention, the controller 540 is capable of including a dualconnectivity processing unit 542 for processing operations in the dualconnectivity mode. For example, the controller 540 is capable ofcontrolling the UE to perform the functions and the procedure describedabove referring to FIG. 2 . In the embodiment, the controller 540performs the following operations.

According to embodiments of the present invention, UE is capable ofperforming operations of the method shown in FIG. 3 under the control ofthe controller 540. For example, when the controller 540 receives a WLANmeasurement instruction message from the eNB, it analyzes the message asin the method shown in FIG. 4 , calculates a frequency to be measured,and performs the measurement for the calculated frequency. When thecontroller 540 ascertains that a preset condition is satisfied based onthe report configuration information comprised in the measurementinstruction message, it is capable of reporting the measurement resultto the eNB.

FIG. 6 is a block diagram showing an ENB in a mobile communicationsystem according to an embodiment of the present invention.

As shown in FIG. 6 , the ENB includes an RF processing unit 610, abaseband processing unit 620, a backhaul communication unit 630, astorage unit 640, and a controller 650.

The RF processing unit 610 performs functions related to thetransmission/reception of signals via a wireless channel, e.g., theconversion of frequency band, the amplification, etc. The RF processingunit 610 up-converts baseband signals output from the basebandprocessing unit 620 into RF band signals and transmits the RF signalsvia an antenna. The RF processing unit 610 down-converts RF band signalsreceived via the antenna into baseband signals. The RF processing unit610 is capable of including a transmission filter, a reception filter,an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. Although theembodiment is shown in FIG. 6 so that the ENB includes only one antenna,it should be understood that the ENB may be implemented to include anumber of antennas. The RF processing unit 610 may also be implementedto include a number of RF chains. The RF processing unit 610 is capableof performing a beamforming operation. In order to perform a beamformingfunction, the RF processing unit 610 is capable of adjusting the phaseand amplitude of individual signals transmitted/received via a number ofantennas or antenna elements.

The baseband processing unit 620 performs the conversion betweenbaseband signals and bitstream according to a physical layerspecification of a first wireless access technology (e.g., cellularnetwork). For example, in the data transmission, the baseband processingunit 620 encodes and modulates a transmission bitstream, therebycreating complex symbols. In the data reception, the baseband processingunit 620 demodulates and decodes baseband signals output from the RFprocessing unit 610, thereby restoring a reception bitstream. Forexample, in the data transmission according to the orthogonal frequencydivision multiplexing (OFDM), the baseband processing unit 620 encodesand modulates a transmission bitstream to create complex symbols, mapsthe complex symbols to sub-carriers, and configures OFDM symbols throughthe inverse fast Fourier transform (IFFT) operation and the cyclicprefix (CP) insertion. In the data reception, the baseband processingunit 620 splits baseband signals output from the RF processing unit 610into OFDM symbol units, restores signals mapped to sub-carriers throughthe fast Fourier transform (FFT) operation, and then restores areception bitstream through the demodulation and the decoding operation.The baseband processing unit 620 and the RF processing unit 610 performthe transmission and reception of signals as described above. Therefore,the baseband processing unit 620 and the RF processing unit 610 may alsobe called a transmitter, a receiver, a transceiver, a communicationunit, a wireless communication unit, etc.

The backhaul communication unit 630 provides interfaces to communicatewith other nodes in the network. That is, the backhaul communicationunit 630 converts: a bitstream into a physical signal to be transmittedto other nodes of the ENB, e.g., another access node, a core network,etc.; and a physical signal received from the nodes into a bitstream.

The storage unit 640 stores a default program for operating the ENB,applications, settings, data, etc. In particular, the storage unit 640is capable of storing information regarding a bearer allocated to theconnected UE, a measurement result reported from the connected UE, etc.The storage unit 640 is capable of providing the dual connectivityfunction to UE or storing reference information to determine whether theENB terminates the dual connectivity operation. The storage unit 640provides the stored data according to the request of the controller 650.

The controller 650 controls all operations of the ENB. For example, thecontroller 650 controls the baseband processing unit 620, the RFprocessing unit 610 and the backhaul communication unit 630 to performthe transmission/reception of signals. The controller 650 controls thestorage unit 640 to store/read data therein/therefrom. To this end, thecontroller 650 is capable of including at least one processor. In theembodiment, the controller 650 performs the following operations.

According to embodiments of the present invention, the eNB is capable ofinstructing UE to measure a frequency via a measurement instructionmessage comprising at least one of the following: Country, OperatingClass, and Channel number, under the control of the controller 650. Inthis case, in order to reduce the consumption of transmission resources,the eNB may create and transmit the measurement instruction messagewithout including Country or Channel number. The measurement instructionmessage may further comprise report configuration information.

Embodiment 2

With reference to FIG. 7 , the LTE system configures the wireless accessnetwork, including evolved node Bs (called ENBs, eNBs, Node Bs or basestations) 705, 710, 715, and 720, a mobility management entity (MME)725, and a serving-gateway (S-GW) 730. user equipment (UE) (which isalso called a terminal) 735 is connected to an external network via theENB 705, 710, 715, or 720 and the S-GW 730. ENBs 705 to 720 correspondto existing Node B of the universal mobile telecommunications system(UMTS). ENBs 705 to 720 are connected to UE 735 via wireless channelsand are capable of performing more complicated functions than existingNode B. In an LTE system, since real-time services such as a voice overinternet protocol (VoIP) service and all user traffic are serviced viashared channels, devices are required to collect information regardingstates, such as buffer states of UE devices, available transmissionpower states, channel states, etc., and to make a schedule. This task isperformed via ENBs 705 to 720. One ENB controls a number of cells. Forexample, in order to implement a transmission rate of 100 Mbps, an LTEsystem employs orthogonal frequency division multiplexing (OFDM) as awireless access technology at a bandwidth of 20 MHz. It also employsadaptive modulation & coding (AMC) to determine modulation scheme andchannel coding rate, meeting with the channel state of UE. The S-GW 730is a device that provides data bearers. The S-GW 730 establishes orremoves data bearers according to the control of the MME 725. The MME725 manages the mobility of UE and controls a variety of functions. TheMME 725 connects to a number of ENBs 705 to 720.

With reference to FIG. 8 , UE and ENB have Packet Data ConvergenceProtocol (PDCP) 805 and 840, Radio Link Control (RLC) 810 and 835, andMedium Access Control (MAC) 815 and 830, respectively. PDCP 805 and 840compress/decompress the IP header. RLC 810 and 835 reconfigure PDCPpacket data unit (PDU) in proper size and perform an Automatic RepeatreQuest (ARQ) operation. MAC 815 and 830 connect to a number of RLClayer devices configured in one UE device. MAC 815 and 830 multiplex RLCPUDs to MAC PDU, and de-multiplex RLC PDUs from MAC PDU. Physical layers(PHY) 820 and 825 in UE and ENB channel-code and modulate data from thehigher layers, create OFDMsymbols, and transmit them via a wirelesschannel. In addition, PHY 820 and 825 demodulate and channel-decode OFDMsymbols transmitted via a wireless channel, and transfer them to thehigher layers.

Dynamic pre-allocation as one of the latency reduction schemes isconsidered.

Pre-allocation is a technique that allows an ENB to allocate, althoughit has not received a transmission resource request from UE, uplinktransmission resources to the UE. Pre-allocation causes a problem thatan ENB allocates, although it has not received a transmission resourcerequest, uplink transmission resources to UE that does not have data tobe transmitted.

In the current specification (rule), although UE does not have data tobe transmitted, when the UE is allocated an uplink grant, it is enforcedto create and transmit a padding MAC PDU. The padding MAC PDU refers toan MAC PDU which includes only padding bits and padding BSR withoutincluding meaningful data. The rule is defined assuming that thefrequency of occurrence of padding MAC PDU is extremely low.

The transmission rule of padding MAC PDU is advantageous because itassists an ENB to control the uplink transmission power and simplifiesthe implementation of a related ENB. When the ENB controls thetransmission power for a UE device, it refers to the statistics ofoccurrence of HARQ ACK/NACK messages in response to MAC PDU transmittedfrom the UE. For example, when HARQ NACK. has never occurred, it meansthat the current transmission power control method is proper. Incontrast, when HARQ NACK occurs relatively frequently, it means that theuplink transmission power control method currently in use needs to bemodified. Embodiments of the present invention provide new operations toUE which is allocated resources but does not perform the transmissionsince it does have data to be transmitted, thereby using thepre-allocation with efficiency. Since a legacy ENB expects a reversetransmission when resources are allocated, it is preferable that thelegacy ENB does not employ new operations described above. In thefollowing description, for the sake of convenience, when a transmissionresource is available, the uplink transmission is unconditionallyperformed, which is called an unconditional transmission operation. Inaddition, although a transmission resource is available, the uplinktransmission is performed only when it satisfies a preset condition,which is called a conditional transmission operation.

Embodiment 2-1

In various embodiments of the present invention, UE selectively employsan unconditional transmission operation or a conditional transmissionoperation according to the instruction of an ENB

A condition as to whether UE employs an unconditional transmissionoperation or a conditional transmission operation needs to bedetermined, cooperating with the implicit release operation ofSemi-Persistent Scheduling (SPS). The implicit release refers to ascheme that enables UE to release the configured uplink grant when thetransmission of MAC PDU without MAC SDU (hereafter called ‘Zero MAC SDUM AC PDU’) is performed successively n times (‘n’ is a positive integer)via an SPS transmission resource. The implicit release is introduced toprovide against the loss of SPS release signals.

Zero MAC SDU MAC PDU is created when UE does not have transmittablehigher layer data. Therefore, when UE employs a conditional transmissionoperation, the implicit release is no longer functioning, which isdisadvantageous. The current standard has been defined to be sure to setthe implicit release for the use of SPS.

Various embodiments of the present invention are capable of selectivelyapplying the conditional transmission operation to an SPS transmissionresource or a normal transmission resource, considering a condition asto whether SPS is configured.

FIG. 9 is a flowchart that describes the operations between UE and ENBaccording to Embodiment 2-1.

In a mobile communication system including UE 905, an ENB 910, and othernodes, the UE establishes the RRC connection with the ENB in operation915. Establishing the RRC connection between ENB and UE means that theENB and UE configure a Signaling Radio Bearer (SRB) SRB therebetween andthus exchange RRC control messages with each other. The RRC connectionis established via a random access process in such a way that: UEtransmits an RRC connection establishment request message to an ENB; theENB transmits an RRC connection establishment message to the UE; and theUE transmits an RRC connection establishment complete message to theENB.

After establishing the RRC connection, the ENB 910 is capable ofinstructing the UE 905 to perform the RRC connection re-configuration inoperation 920. The ENB is capable of transmitting the SPS configurationinformation to the UE via the RRC connection re-configuration message,and instructing the UE on the condition as to whether it employs theconditional transmission operation. The Information indicating acondition as to whether UE employs the conditional transmissionoperation may be comprised in the lower information of sps-ConfigUL orMAC-MainConfig of the RRCConnectionReconfiguration message, and may bedefined as the format of ENUMERATED {SETUP}, calledSkipUplinkTransmission (SkipULTx). For example, when sps-ConfigUL orMAC-MainConfig of the RRCConnectionReconfiguration message received bythe UE comprises SkipUplinkTransmission (SkipULTx) indicated by SETUP,it means that the UE is instructed to perform a conditional transmissionoperation. On the other hand, when sps-ConfigUL or MAC-MainConfig of theRRCConnectionReconfiguration message does not compriseSkipUplinkTransmission (SkipULTx), it means that the UE is instructed toperform an unconditional transmission operation.

The SPS configuration information is defined as follows.

 SPS-Config ::=  SEQUENCE {  semiPersistSchedC-RNTI C-RNTI OPTIONAL,  -Need OR  sps-ConfigDL  SPS-ConfigDL  OPTIONAL,  --Need ON  sps-ConfigUL OPTIONAL  -- Need ON  }  ...  SPS-ConfigUL ::=  CHOICE {  release NULL,  setup  SEQUENCE {  semiPersistSchedIntervalUL  ENUMERATED { sf10, sf20, sf32, sf40, sf64, sf80,  sf128, sf160, sf320, sf640,spare6,  spare5, spare4, spare3, spare2,  spare1 }, implicitReleaseAfter  ENUMERATED {e2, e3, e4, e8},  p0-Persistent SEQUENCE {  p0-NominalPUSCH-Persistent  INTEGER (-126..24), p0-UE-PUSCH-Persistent  INTEGER (-8..7)  } OPTIONAL,  -- Need OP twoIntervalsConfig ENUMERATED {true}OPTIONAL,  --Cond TDD  ...,  [[p1-PersistentSubframoSet2-rl2   CHOICE {  release   NULL,  setup   SEQUENCE- {  p0-NominalPUSCH-PersistentSubframeSet2-r12      INTEGER(-126..24),  p0-UE-PUSCH-PersistentSubframeSet2-r12 INTEGER (-8..7)  } } OPTIONAL - Need ON  ]]  }  }  N1PUCCH-AN-PersistentList ::=  SEQUENCE (SIZE (1..4))  OF  INTEGER  (0..2047)  - ASN 1 STOP

TABLE 2-1   SPS-Config field descriptions   implicitReleaseAfter  Number of empty transmissions before implicit release, see TS 36.321[6, 5.10.2], Value e2 corresponds to 2 transmissions, e3 corresponds to3 transmissions and so on.   n1 PUCCH-AN-PersistentList, n1PUCCH-AN-PersistentListP1   List of parameter: for antenna port P0 andfor antenna port P1 respectively, see TS 36.213 [23, 10.1].  Field n1-PUCCH-AN-PersistentListP1 is applicable only if thetwoAntennaPortActivatedPUCCH-Format1a1b in PUCCH-ConfigDedicated-v1020is set to true. Otherwise the field is not configured.  numberOfConfSPS-Processes   The number of configured HARQ processesfor Semi-Persistent Scheduling, see TS 36.321 [6].  p0-NominalPUSCH-Persistent   Parameter: . See TS 36.213 [23, 5.1.1.1],unit dBm step 1. This field is applicable for persistent scheduling,only. If choice setup is used and p0-Persistent is absent, apply thevalue of p0-NominalPUSCH for p0-NominalPUSCH-Persistent. If uplink powercontrol subframe sets are configured by tpc-SubframeSet, this fieldapplies for uplink power control subframe set 1.  p0-Nominal-PUSCH-PersistentSubframeSet2   Parameter: . See TS 36.213[23, 5.1.1.1], unit dBm step 1. This field is applicable for persistentscheduling, only. If p0-PersistentSubframeSet2-r12 is not configured,apply the value of p0-NominalPUSCH-SubframeSet2-r12 forp0-NominalPUSCH-PersistentSubframeSet2. E-UTRAN configures this fieldonly if uplink power control subframe sets are configured bytpc-SubframeSet, in which case this field applies for uplink powercontrol subframe set 2.   p0-UE-PUSCH-Persistent   Parameter: . See TS36.213 [23, 5.1.1.1], unit dB. This field is applicable for persistentscheduling, only. If choice setup is used and p0-Persistent is absent,apply the value of p0-UE-PUSCH for p0-UE-PUSCH-Persistent. If uplinkpower control subframe sets are configured by tpc-SubframeSet, thisfield applies for uplink power control subframe set 1.  p0-UE-PUSCH-PersistentSubframeSet2   Parameter: See TS 36.213 [23,5.1.1.1], unit dB. This field is applicable for persistent scheduling,only. If p0-PersistentSubframeSet2-r12 is not configured, apply thevalue of p0-UE-PUSCH-SubframeSet2 forp0-UE-PUSCH-PersistentSubframeSet2. E-UTRAN configures this field onlyif uplink power control subframe sets are configured by tpc-SubframeSet,in which case this field applies for uplink power control subframe set2.   semiPersistSchedC-RNTI   Semi-persistent Scheduling C-RNTI, see TS36.321 [6].   semiPersistSchedIntervalDL   Semi-persistent schedulinginterval in downlink, see TS 36.321 [6]. Value in number of sub-frames.Value sf10 corresponds to 10 sub-frames, sf20 corresponds to 20sub-frames and so on. For TDD, the UE shall round this parameter down tothe nearest integer (of 10 sub-frames), e.g. sf10 corresponds to 10sub-frames, sf32 corresponds to 30 sub-frames, sf128 corresponds to 120sub-frames.   semiPersistSchedIntervalUL   Semi-persistent schedulinginterval in uplink, see TS 36.321 [6]. Value in number of sub-frames.Value sf10 corresponds to 10 sub-frames, sf20 corresponds to 20sub-frames and so on. For TDD, the UE shall round this parameter down tothe nearest integer (of 10 sub-frames), e.g. sf10 corresponds to 10sub-frames, sf32 corresponds to 30 sub-frames, sf128 corresponds to 120sub-frames.   twolntervalsConfig   Trigger oftwo-intervals-Semi-Persistent Scheduling in uplink. See TS 36.321 [6,5.10]. If this field is present, two-intervals-SPS is enabled foruplink. Otherwise, two-intervals-SPS is disabled.

TABLE 2-2 Conditional presence Explanation TDD This field is optionalpresent for TDD, need OR; it is not present for FDD and the UE shalldelete any existing value for this field.

When an uplink transmission resource allocated for new transmission isavailable in operation 925, UE determines whether the uplinktransmission is performed in operation 930. The uplink transmissionresource allocated for new transmission may be a transmission resourcewhich is allocated via PDCCH addressed by a C-RNTI of UE or atransmission resource for SPS, i.e., configured UL grant.

UE: determines whether it performs the transmission via the uplinktransmission resource (or whether it creates MAC PDU to be transmittedvia the uplink transmission resource), considering a condition as towhether SPS-ConfigUL (first information) and SkipUplinkTransmission(second information) exit, a characteristic of an available transmissionresource, a condition as to whether uplink data to be transmittedexists, a characteristic of uplink data to be transmitted, etc.; andperforms or does not perform the uplink transmission, based on thedetermination in operation 930.

FIG. 10 is a flowchart that describes operations of UE according toEmbodiment 2-1.

UE receives a control message, RRCConnectionReconfiguration, inoperation 1005.

UE determines whether an IE of the control message comprises secondcontrol information in operation 1010.

When UE ascertains that an IE of the control message comprises secondcontrol information in operation 1010, it determines to apply theconditional transmission operation to the transmission and waits until atime that a new uplink transmission can be performed in operation 1015.When a new uplink transmission can be performed (e.g., when a configureduplink grant is available or an uplink grant is received via PDCCH), UEproceeds with operation 1025.

On the other hand, when UE ascertains that an IE of the control messagedoes not comprise second control information in operation 1010, i.e.,when UE employs the conditional transmission operation, it may return tothe unconditional transmission operation in operation 1020. That is, theconditional transmission operation is initiated when an RRC connectionreconfiguration message including an IE where second control informationis comprised is received. When an RRC connection reconfiguration messageincluding an IE where second control information is not comprised isreceived, UE is released and returns to the unconditional transmissionoperation. After that, UE proceeds with operation 1040. The IE may beSPS-ConfigUL or MAC-MainConfig.

In operation 1025, UE determines whether the new uplink transmission isa transmission via an SPS transmission resource (or a new transmissionvia a configured reverse grant) or a transmission via an allocateduplink grant on PDCCH addressed by a C-RNTI (or a new transmission via adynamically allocated transmission resource). When UE ascertains thatthe new uplink transmission is a transmission via an SPS transmissionresource in operation 1025, it employs a first operation in operation1030. When UE ascertains that the new uplink transmission is atransmission via an allocated uplink grant on PDCCH in operation 1025,it employs a second operation in operation 1035.

The first operation may be a conditional transmission operation or anunconditional transmission operation. The second operation may be aconditional transmission operation or an unconditional transmissionoperation.

Operations 1025, 1030, and 1035 mean that a conditional transmissionoperation may be employed selectively according to types of uplinktransmission. For example, although second control information has beenconfigured, a conditional transmission operation is applied to theuplink transmission only when the uplink transmission is a transmissionvia SPS, and an unconditional transmission operation is applied to theuplink transmission only when the uplink transmission is a transmissionvia a dynamically allocated transmission resource on PDCCH (whenoperation 1030 corresponds to a conditional transmission and operation1035 corresponds to an unconditional transmission). Alternatively, theuplink transmission may employ: an unconditional transmission operationwhen the uplink transmission is a transmission via SPS; and aconditional transmission operation when the uplink transmission is atransmission via a dynamically allocated transmission resource on PDCCH.Alternatively, all the transmissions may employ a conditionaltransmission operation, regardless of types of transmission (whenoperation 1030 corresponds to an unconditional transmission andoperation 1035 corresponds to a conditional transmission).

When an uplink grant allowing for a new uplink transmission is availablein operation 1040, UE applies an unconditional transmission operation tothe uplink transmission in operation 1045.

In the following description, rules of the conditional transmissionoperation and the unconditional transmission operation according tovarious embodiments of the present invention are explained.

Conditional Transmission Operation

When MAC SDU available for transmission exists or transmittable MACcontrol element (MAC CE) except for BSR included for padding (paddingBSR) exists, UE performs the uplink transmission (or UE performs afollowing procedure for creating MAC PDU, considering that a validuplink grant exists).

When MAC SDU available for transmission does not exist (i.e., dataavailable for transmission does not exist in both PDCP device and RLCdevice) and transmittable MAC CE except for padding BSR does not exist,UE does not perform the uplink transmission (or UE does not perform afollowing procedure for creating MAC PDU, considering that a validuplink grant does not exist).

Rule No. 2 of the conditional transmission operation may be modified insuch a way that: although MAC SDU available for transmission does notexist and transmittable MAC CE except for padding BSR does not exist,when a serving cell to perform new transmission is scheduled, in the TTIinstructed to perform new transmission, along with the transmission onPUCCH, such as HARQ ACK/NACK or CQI/PMI/RI, UE performs the uplinktransmission; and in a state where MAC SDU available for transmissiondoes not exist and transmittable MAC CE except for padding BSR does notexist, the uplink transmission may be omitted only when a simultaneoustransmission along with the transmission on PUCCH is not scheduled in acorresponding TTI. Since the PUCCH transmission is performed using aPUCCH transmission resource and part of the PUSCH transmission resource,when UE does not perform the PUSCH transmission in the conditiondescribed above, the eNB may not correctly receive the PUCCH.

Unconditional Transmission Operation

When MAC CE or MAC SDU available for transmission exists, UE creates andtransmits a general MAC PDU. When MAC CE or MAC SDU available fortransmission does not exist, UE creates and transmits a padding MAC PDUconfigured with only padding and a padding BSR.

In the following description, rules related to the implicit release ofSPS according to various embodiments of the present invention areexplained.

According to various embodiments of the present invention, when theconditional transmission and the SPS have been configured, UE does notemploy the implicit release of SPS. When the SPS has been configured, UEemploys the implicit release of SPS. As described above, since theinformation, implicitReleaseAfter, is not omitted in the SPSconfiguration information, the implicitReleaseAfter is used or ignoredaccording to a condition as to whether the conditional transmission isconfigured.

More specifically, when UE receives an RRC control message comprisingfirst information, it determines whether the control message comprisessecond control information or has employed a conditional transmissionoperation (i.e., when UE received the second control information). WhenUE ascertains that the control message does not comprise second controlinformation or has not employed a conditional transmission operation, itemploys the implicit release, considering implicitReleaseAfter comprisedin the first information (or uses the implicit release technique). Onthe other hand, when UE ascertains that the control message comprisessecond control information or has already employed a conditionaltransmission operation, it does not employ the implicit release,ignoring implicitReleaseAfter comprised in the first control informationsince the time when the UE received the second control information. Thatis, although UE transmits Zero MAC SDU MAC PDU a number of times,implicitReleaseAfter, via the SPS transmission resource, it does notrelease the SPS. The Zero MAC SDU MAC PDU is referred to as MAC PDUwithout MAC SDU.

In the following description, the padding MAC PDU and Zero MAC SDU MACPDU are explained.

The Zero MAC SDU MAC PDU may comprise all the MAC CEs listed as follows.

TABLE 3 Index LCID values 10110 Truncated Sidelink BSR 10111 SidelinkBSR 11000 Dual Connectivity Power Headroom Report 11001 Extended PowerHeadroom Report 11010 Power Headroom Report 11011 C-RNTI 11100 TruncatedBSR 11101 Short BSR 11110 Long BSR 11111 Padding

On the other hand, the padding MAC PDU may comprise padding MAC CEs andpadding BSRs. The padding BSR may be Truncated BSR, Short BSR, or LongBSR, according to the size of padding space, as follows. Detailed BSRsare as follows.

TABLE 4 Index LCID values 10110 Truncated Sidelink BSR 10111 SidelinkBSR 11100 Truncated BSR 11101 Short BSR 11110 Long BSR 11111 Padding

Embodiment 2-2

In various embodiments of the present invention, UE selectively employsan unconditional transmission operation or a conditional transmissionoperation according to the instruction of an ENB.

In various embodiments of the present invention, UE selectively employsan unconditional transmission operation or a conditional transmissionoperation according to types of a reverse transmission resource.

When UE can use a transmission resource to which a conditionaltransmission operation is applied, it determines whether the New DataIndicator (NDI) is toggled, based on the presence of data to betransmitted, and controls a condition as to whether it performs a newtransmission.

The present invention is capable of selectively applying the conditionaltransmission operation to an SPS transmission resource or a normaltransmission resource, considering a condition as to whether SPS isconfigured.

FIG. 11 is a flowchart that describes the operations between UE and ENBaccording to Embodiment 2-2.

In a mobile communication system including UE 1105, an ENB 1110, andother nodes, the UE establishes the RRC connection with the ENB inoperation 1115. Establishing the RRC connection between ENB and UE meansthat the ENB and UE configure a Signaling Radio Bearer (SRB) SRBtherebetween and thus exchange RRC control messages with each other. TheRRC connection is established via a random access process in such a waythat: UE transmits an RRC connection establishment request message to anENB; the ENB transmits an RRC connection establishment message to theUE; and the UE transmits an RRC connection establishment completemessage to the ENB.

After establishing the RRC connection, the ENB 1110 is capable ofinstructing the UE 1105 to perform the RRC connection re-configurationin operation 1120. The ENB is capable of providing the UE with first andsecond information via the RRC connection re-configuration message,instructing the UE to perform a conditional transmission operation.

The first information is referred to as information indicating acondition as to whether a conditional transmission operation is appliedto a dynamic grant and is formed by 1 bit. When UE is signaled with 1bit, the UE applies a conditional transmission operation to a dynamicgrant. When UE is not signaled with 1 bit, the UE applies anunconditional transmission operation to a dynamic grant. The dynamicgrant is referred to as a grant that is allocated on PDCCH and is usedonce only for the first transmission. In the following description, thefirst information is expressed as SkipULTxDynamic.

The second information is referred to as information indicating acondition as to whether a conditional transmission operation is appliedto a configured grant and is formed by 1 bit. When UE is signaled with 1bit, the UE applies a conditional transmission operation to a configuredgrant. When UE is not signaled with 1 bit, the UE applies anunconditional transmission operation to a configured grant. Theconfigured grant is referred to as a grant that SPS is applied to andthat is, once it is allocated on PDCCH, used a number of times for thefirst transmission until it is released. In the following description,the second information is expressed as SkipULTxSPS.

When an uplink transmission resource allocated for new transmission isavailable in operation 1125, UE determines whether the uplinktransmission is performed in operation 1130. The uplink transmissionresource allocated for new transmission may be a transmission resourcewhich is allocated via PDCCH addressed by a C-RNTI of UE or atransmission resource for SPS, i.e., configured UL grant.

UE: determines whether it performs the transmission via the uplinktransmission resource (or whether the NDI related to the uplinktransmission resource is toggled), considering a condition as to whetherthe first information is configured (exists), a condition as to whetherthe second information is configured (exists), a type of an availabletransmission resource, a condition as to whether uplink data to betransmitted exists, a characteristic of uplink data to be transmitted,etc.; and performs or does not perform the uplink transmission, based onthe determination in operation 1130.

FIG. 12 is a flowchart that describes operations of UE.

UE receives an RRC connection re-configuration control message,RRCConnectionReconfiguration, in operation 1205. UE re-configures theRRC connection according to the received control message. For example,when the RRC connection re-configuration message comprises SPSconfiguration information, UE configures SPS and performs the SPSrelated operation. The control message may comprise information relatedto the conditional transmission described above.

When UE needs to perform the uplink transmission, e.g., when UE isinstructed to perform the uplink transmission on PDCCH or when a timethat a configured uplink grant is available is reached, in operation1210, the UE determines whether the related uplink grant is a configuredgrant or a dynamic grant received on PDCCH in operation 1215. When theUE ascertains that the related uplink grant is a dynamic grant receivedon PDCCH in operation 1215, it proceeds with operation 1220. When the UEascertains that the related uplink grant is a configured grant inoperation 1215, it proceeds with operation 1240.

UE determines whether SkipTxDynamic is configured in operation 1220.When UE ascertains that SkipTxDynamic is configured in operation 1220,it proceeds with operation 1225.

When UE ascertains that SkipTxDynamic is not configured in operation1220, it proceeds with operation 1265.

UE determines whether it satisfies the following condition in operation1225. When UE satisfies the following condition in operation 1225, itproceeds with operation 1230. When UE does not satisfy the followingcondition in operation 1225, it proceeds with operation 1235.

Condition

Data available for transmission exists, and an NDI of the related HARQprocess differs from the previous value (or is toggled).

The NDI is managed per HARQ process and controls the HARQ operation. AnHARQ device determines whether an NDI is changed, and distinguishesbetween a new transmission and the re-transmission, based on thedetermination.

UE triggers the HARQ re-transmission in operation 1230. The triggeredHARQ re-transmission is connected to the HARQ re-transmission at atiming.

UE triggers the first HARQ transmission in operation 1235. The triggeredfirst HARQ transmission may be connected to the first HARQ transmissionat a timing.

UE determines whether SkipTxSPS is configured in operation 1240. WhenSkipTxSPS is configured in operation 1240, UE proceeds with operation1245. When SkipTxSPS is not configured in operation 1240, UE proceedswith operation 1265.

UE determines whether it satisfies the following condition in operation1245. When UE satisfies the following condition in operation 1245, itproceeds with operation 1250. When UE does not satisfy the followingcondition in operation 1245, it proceeds with operation 1260.

Condition

Data available for transmission exists.

UE considers that an NDI of a corresponding HARQ process is toggled inoperation 1250, and triggers the first transmission in operation 1255.That is, when data available for transmission exists, withoutconsidering an actual NDI for a configured transmission resource, UEconsiders that the NDI has been toggled and triggers a new transmission.

UE does not consider that an NDI has been toggled, and does not triggernew transmission in operation 1260. That is, in a state where SkipTxSPShas been configured, when data available for transmission does not existdespite of the presence of a configured uplink grant, UE does notconsider that an NDI is toggled and does not trigger a new transmission.

UE operates in the same way as prior art in operation 1265. That is, UEperforms the reverse transmission, according to an instructed reversegrant or configured reverse grant, regardless of the presence of dataavailable for transmission.

In the embodiment of the present invention, when data available fortransmission exists, it means that data available for transmissionexists in a higher layer or MAC CE, except for truncated BSR or paddingBSR, exists. The higher layer data available for transmission may bereferred to as PDCP SDU, PDCP PDU, RLC SDU, and RLC PDU.

Embodiment 2-3

With the evolution of mobile communication systems, the minimization ofthe uplink delay has become as an important issue. The present inventionprovides a shared SPS scheme for reducing the uplink relay.

Most part of the uplink delay is caused in processes where UE requeststhe allocation of a transmission resource and the transmission resourceis allocated. In a state where UE is successively allocated an SPStransmission resource, when data is created, the UE is capable ofperforming the rapid transmission of the data. However, when SPStransmission resources are dedicatedly allocated to all UE devices, thetransmission resources are excessively consumed. In order to resolve theproblem, various embodiments of the present invention introduce a sharedSPS scheme that allocates the same SPS transmission resource to a numberof UE devices. UE devices configured with shared SPS perform thetransmission of data only when they have data to be transmitted. UEdevices configured with shared SPS monitor PDCCH and apply different UEidentifiers to the uplink scrambling, so that the ENB can identifyuplink data from UE devices, respectively. Since the shared SPS schemeuses only a small part of the given resources, it is preferable that thescheme is applied to a small cell abundant in transmission resources.Therefore, the shared SPS scheme is used for a serving cell specified byan ENB, unlike general SPS schemes.

FIG. 13 is a flowchart that describes the operations between UE and ENBaccording to Embodiment 2-3.

In a mobile communication system includes UE 1305, an ENB 1310 and othernodes, the UE establishes the RRC connection with the ENB in operation1315. Establishing the RRC connection between UE and ENB means that theENB and UE configures a Signaling Radio Bearer (SRB) therebetween andthus exchange RRC control messages with each other. The RRC connectionis established via a random access process in such a way that: UEtransmits an RRC connection establishment request message to an ENB; theENB transmits an RRC connection establishment message to the UE; and theUE transmits an RRC connection establishment complete message to theENB.

After establishing the RRC connection, the ENB 1310 is capable oftransmitting, to the UE 1305, a UECapabilityEnquiry control messageinstructing the UE 1305 to report the UE capability, if it is necessary,in operation 1520. The control message comprises the field of a RadioAccess Technology (RAT) type, indicating a capability regarding an RAT,from among the capabilities of UE. When the ENB is reported a capabilityregarding EUTRA, the ENB sets the RAT Type to EUTRA.

When receiving the UECapabilityEnquiry control message where the RATType is set to EUTRA, UE 1305 transmits, to the ENB 1310, aUECapabilityInformation control message comprising the UE’s capabilityinformation regarding EUTRA in operation 1325.

The control message comprises UE-EUTRA-Capability. TheUE-EUTRA-Capability comprises a name list of features supported by UE,categories of UE (ue-Category), a combination of frequency bandssupported by UE (supportedBandCombination), etc. UE supports a sharedSPS function. When UE has completed the inter-Operability Test for theshared SPS function, it may include an IE representing that it cansupport the shared SPS function in the control message.

When the ENB 1310 ascertains that the latency reduction needs to beapplied to the UE 1305, it is capable of instructing the UE 1305 toperform the RRC connection reconfiguration in operation 1330). The ENBis capable of transmitting the shared SPS configuration information tothe UE, via the RRC connection reconfiguration message. The shared SPSconfiguration information is formed with SPS-Config information andSPS-Config-ext.

The structure of the SPS-Config may be identical to the SPSconfiguration information described above in the section of Embodiment2-1.

The structure of the SPS-Config-ext is as follows.

  SPS-Config-ext ::=   SEQUENCE {   semiPersistSchedC-RNTI2 C-RNTOPTIONAL,   semiPersistSchedIntervalUL2 ENUMERATED {   sf1, sf2, sf4,sf6, sf8, spare3, spare2,   spare1 },   logicalChannelIdList...  SharedSPSenabledCell ServCellIndex   }   ...

In summary, SPS-Config may comprise the following IEs:

-   first SPS C-RNTI (semiPersistSchedC-RNTI)-   first interval (semiPersistSchedIntervalUL)-   automatic release parameter (semiPersistSchedC-RNTI)

For example, SPS-Config-ext may comprise the following IEs:

-   Shared SPS indicator (SPS-Config-ext may serve as a shared SPS    indicator or an additional indicator may be employed)-   second SPS C-RNTI (semiPersistSchedC-RNTI2)-   second interval (semiPersistSchedIntervalUL2)-   Logical channel list (logicalChannelIdList): a name list of logical    channels capable of using a shared SPS-   serving cell id (SharedSPSenabledCell): an identifier of a serving    cell where a shared SPS will be activated/employed

UE 1305 monitors whether the SPS function is activated in operation1335. UE 1305 monitors whether a general SPS and a shared SPS areactivated, respectively.

Setting a general SPS function to a UE device means that: onlySPS-config is set to UE at a corresponding timing but SPS-config-ext isnot set thereto. This corresponds to the following cases: UE hasreceived an rrcConnectionReconfiguration message comprising validSPS-config from the ENB; UE has not released the received SPS-config; UEhas not received the SPS-Config-ext; and UE received the SPS-Config-extbut has already released the SPS-Config-ext. For example, when UE, notset with an SPS, receives an rrcConnectionReconfiguration controlmessage that comprises only SPS-config but does not compriseSPS-Config-ext, it is set with a general SPS.

Setting a shared SPS function to a UE device means that: SPS-config andSPS-config-ext are set to UE at a corresponding timing. This correspondsto the following cases: UE has received an rrcConnectionReconfigurationmessage comprising valid SPS-config and valid SPS-Config-ext from theENB; and UE has not released the received SPS-config and the receivedSPS-Config-ext. For example, when UE, not set with an SPS, receives anrrcConnectionReconfiguration control message that comprises SPS-configand SPS-Config-ext, it is set with a shared SPS.

UE set with a general SPS monitors PDCCH of PCell or PSCell (hereaftercommonly called SpCell) and determines whether SPS is activated. Whentill receives an uplink grant, via a first SPS C-RNTI, on the PDCCH ofSpCell, it checks a new data indicator (NDI) of the uplink grant. Whenthe NDI is ‘0’ and information regarding the PDCCH is not informationspecifying the release, UE stores the uplink grant and the associatedHARQ information as configured uplink grant, and initiates the SPSoperation.

Via a PDCCH of a serving cell specified as SharedSPSenabledCell or via aPDCCH of a scheduling cell of the serving cell (refer to the cellCrossCarrierSchedulingConfig which provides scheduling informationregarding the serving cell) in a state where a cross-carrier schedulingis employed, when UE set with a shared SPS receives uplink grant, via anSPS C-RNTI for the monitoring, it checks an NDI of the uplink grant.When the NDI is ‘0’ and information regarding the PDCCH is notinformation specifying the release, UE stores the uplink grant and theassociated HARQ information as configured uplink grant, and initiatesthe shared SPS operation.

The SPS C-RNTI for the monitoring may be first SPS C-RNTI or second SPSC-RNTI.

In a general SPS operation, the SPS C-RNTI for monitoring an SPSactivation signal is identical to the SPS C-RNTI for the scrambling onPUSCH. That is, UE monitors the PDCCH by using one SPS C-RNTI as a firstSPS C-RNTI, and scrambles the uplink data.

In a shared SPS operation, an SPS C-RNTI for monitoring PDCCH and an SPSC-RNTI for scrambling the uplink data are separated from each other. Forexample, PDCCH is monitored by a first SPS-CRNTI and PUSCH is scrambledby a second SPS C-RNTI. Alternatively, PDCCH is monitored by a secondSPS-CRNTI and PUSCH is scrambled by a first SPS C-RNTI. These operationsare separately performed because an SPS C-RNTI for the monitoring is anidentifier which is commonly applied to a number of UE devices, and thusan ENB cannot identify, when uplink data is scrambled with the SPSC-RNTI for the monitoring, UE transmitting the uplink data. Therefore,an SPS C-RNTI for the uplink scrambling employs a UE specific SPSC-RNTI. That is, an ENB allocates the same value to an SPS C-RNT for themonitoring for a number of UE devices in a shared SPS. On the otherhand, the ENB allocates unique values to SPS C-RNTIs for the scramblingfor UE devices, respectively.

Scrambling PUSCH by using an SPS C-RNTI is defined in the TS 36.212 andTS 36.213.

When UE receives an uplink grant instructing to initiate a general SPSoperation or a shared SPS operation in operation 1340, it initiates ageneral SPS operation or a shared SPS operation in operation 1345.

In the following description, a general SPS operation is explained.

UE performs the uplink transmission, using an SPS resource, at a cycleof semiPersistSchedIntervalUL (a cycle included in the SPS-config) inSpCell, based on a sub-frame initiating an SPS operation. For example,UE ascertains that the Nth grant has been created in a sub-frame of anSpCell, and performs the uplink transmission by applying a correspondinggrant to the sub-frame.

Although UE does not have data to be transmitted at a correspondingtiming when transmitting an MAC PDU via the SPS resource, it creates andtransmits a padding MAC PDU including BSR MAC CE and Padding MAC CE. TheUE may apply a first SPS C-RNTI to the scrambling operation for theuplink transmission.

When only Zero MAC SDU MAC PDU is transmitted for a number of times,implicitReleaseAfter, UE releases the configured uplink grant.

In the following description, a shared SPS operation is explained.

UE performs the uplink transmission, using a shared SPS resource, at acycle of semiPersistSchedIntervalUL2 (a cycle included in theSPS-config-ext) in the SharedSPSenabledCell, based on a sub-frameinitiating an SPS operation. For example, UE ascertains that the Nthgrant has been created in a sub-frame of an SpCell, and performs theuplink transmission by applying a corresponding grant to the sub-frame.

When UE does not have ‘data available for transmission via a shared SPStransmission resource’ at a corresponding timing that MAC PDU istransmitted via the SPS resource, it does not perform the uplinktransmission. Although only Zero MAC SDU MAC PDU has been transmittedfor a number of times, implicitReleaseAfter, UE does not release theconfigured uplink grant. The Zero MAC SDU MAC PDU is referred to as MACPDU that comprises only MAC CE but does not comprise MAC SDU comprisinghigh layer data. UE performs the scrambling for the uplink transmissionby employing an SPS C-RNTI that differs from an SPS C-RNTI used tomonitor PDCCH. The SPS C-RNTI applied to the scrambling may be a C-RNTIof the UE. That is, the identifier may be formed in various combinationsas in the following Table 5.

TABLE 5 Identifier for monitoring PDCCH Identifier for scrambling uplinksemiPersistSchedC-RNTI of SPS-config semiPersistSchedC-RNTI2 ofSPS-config-ext semiPersistSchedC-RNTI2 of SPS-config-extsemiPersistSchedC-RNTI of SPS-config semiPersistSchedC-RNTI ofSPS-config C-RNTI of mobilityControlInfo or C-RNTI allocated in the RRCconnection configuration

In table 5, the last row is a case where SPS C-RNTI 2 is not allocatedin SPS-config-ext. In this case, UE scrambles the shared SPS uplinktransmission, using its C-RNTI, i.e., its UE specific identifier.

As described above, UE is capable of transmitting only data of a logicalchannel, logicalChannelIdList, via a shared SPS transmission resource.Although UE has data of other logical channels (e.g., RRC messages,etc.), except for the data of the logicalChannelIdList, it does notconsider the data to be ‘data available for transmission via a sharedSPS transmission resource’ but considers only data of a logical channelof the logicalChannelIdList to be ‘data available for transmission via ashared SPS transmission resource.’

When UE 1305 receives the uplink grant indicating the SPS release inoperation 1350, it terminates the SPS operation and releases theconfigured uplink grant or the configured shared uplink grant.

FIG. 14 is a flowchart that describes operations of UE according toEmbodiment 2-3.

UE has not received valid SPS-config; or although UE received validSPS-config, it has already released the SPS-config. This UE receives acontrol message, RRCConnectionReconfiguration, in operation 1405.

UE determines whether the control message comprises SPS-config andSPS-config-ext in operation 1410. When UE ascertains that the controlmessage comprises both SPS-config and SPS-config-ext in operation 1410,it performs operations related to a shared SPS in operation 1415.

When UE ascertains that the control message comprises only SPS-config inoperation 1410, it performs operations related to a general SPS inoperation 1420.

The operations related to a shared SPS and operations related to ageneral SPS are described as in the following table 6.

TABLE 6 Operations related to a general SPS Operations related to ashared SPS Monitor PDCCH of SpCell Monitor PDCCH of SharedSPSenabledCellDetermine whether to receive an uplink grant instructing to initiate ageneral SPS operation by using semiPersistSchedC-RNTI allocated inSPS-config Determine whether to receive an uplink grant instructing toinitiate operations related to a shared SPS operation by using anidentifier for monitoring PDCCH Apply an SPS cycle tosemiPersistSchedlntervalUL of SPS-config Apply an SPS cycle tosemiPersistSchedIntervalUL2 of SPS-config-ext Scramble the transmissionof PUSCH via an SPS resource, by using ‘semiPersistSchedC-RNTI allocatedin SPS-config’ Scramble the transmission of PUSCH via an SPS resource,by using an ‘identifier for uplink scrambling′’ Transmit uplink data viaPUSCH of SpCell Transmit uplink data via PUSCH of SharedSPSenabledCellTransmit padding MAC PDU when there is no data available fortransmission Omit the transmission when there is no data available fortransmission Release an SPS transmission resource when ‘Zero MAC SDU MACPDU’ is successively transmitted a preset number of times Maintain anSPS transmission resource although ‘Zero MAC SDU MAC PDU’ issuccessively transmitted a preset number of times

The following table 7 shows operations according to another embodiment.

TABLE 7 Operations related to a general SPS Operations related to ashared SPS Monitor PDCCH of SpCell Monitor PDCCH of SpCell MonitorDedicated Search Space of SpCell PDCCH Monitor Common Search Space ofSpCell PDCCH Determine whether to receive uplink grant instructing toinitiate a general SPS operation by using semiPersistSchedC-RNTIallocated in SPS-config Determine whether to receive uplink grantinstructing to initiate operations related to a shared SPS operation byusing an identifier for monitoring PDCCH

The common search space and dedicated search space follow TS 36.211,36.212, and 36.213.

FIG. 15 is a block diagram showing of the configuration of UE accordingto Embodiment 2 of the present invention.

With reference to FIG. 15 , the UE includes a Radio Frequency (RF)processing unit 1510, a baseband processing unit 1520, a storage unit1530, and a controller 1540.

The RF processing unit 1510 performs functions relates to thetransmission/reception of signals via a wireless channel, e.g., theconversion of frequency band, the amplification, etc. The RF processingunit 1510 up-converts baseband signals output from the basebandprocessing unit 1520 into RF band signals and transmits the RF signalsvia an antenna. The RF processing unit 1510 down-converts RF bandsignals received via the antenna into baseband signals. The RFprocessing unit 1510 is capable of including a transmission filter, areception filter, an amplifier, a mixer, an oscillator, a digital toanalog convertor (DAC), an analog to digital convertor (ADC), etc.Although the embodiment is shown in FIG. 15 so that the UE includes onlyone antenna, it should be understood that the UE may be implemented toinclude a number of antennas. The RF processing unit 1510 may also beimplemented to include a number of RF chains. The RF processing unit1510 is capable of performing a beamforming operation. In order toperform a beamforming function, the RF processing unit 1510 is capableof adjusting the phase and amplitude of individual signalstransmitted/received via a number of antennas or antenna elements. TheRF processing unit 1510 is capable of performing MIMO and receiving anumber of layers in MIMO.

The baseband processing unit 1520 performs the conversion betweenbaseband signals and bitstream according to a physical layerspecification (rule) of the system. For example, in the datatransmission, the baseband processing unit 1520 encodes and modulates atransmission bitstream, thereby creating complex symbols. In the datareception, the baseband processing unit 1520 demodulates and decodesbaseband signals output from the RF processing unit 1510, therebyrestoring a reception bitstream. For example, in the data transmissionaccording to the orthogonal frequency division multiplexing (OFDM), thebaseband processing unit 1520 encodes and modulates a transmissionbitstream to create complex symbols, maps the complex symbols tosub-carriers, and configures OFDM symbols through the inverse fastFourier transform (IFFT) operation and the cyclic prefix (CP) insertion.In the data reception, the baseband processing unit 1520 splits basebandsignals output from the RF processing unit 1510 into OFDM symbol units,restores signals mapped to sub-carriers through the fast Fouriertransform (FFT) operation, and then restores a reception bitstreamthrough the demodulation and decoding operation.

The baseband processing unit 1520 and the RF processing unit 1510perform the transmission and reception of signals as described above.Therefore, the baseband processing unit 1520 and the RF processing unit1510 may also be called a transmitter, a receiver, a transceiver, acommunication unit, etc. In addition, the baseband processing unit 1520and/or the RF processing unit 1510 may include a number of communicationmodules to support wireless access technologies that differ from eachother. Alternatively, the baseband processing unit 1520 and/or the RFprocessing unit 1510 may include different communication modules toprocess signals of different frequency bands. Examples of the wirelessaccess technologies include wireless LAN (e.g., IEEE 802.11), a cellularnetwork (e.g., LTE), etc. Examples of the different frequency bandsinclude super high frequency (SHF) (e.g., 2.5 GHz band, 5 GHz band,etc.), millimeter wave (mmW) (e.g., 60 GHz band), etc.

The storage unit 1530 stores a default program for operating the UE,applications, settings, data, etc. In particular, the storage unit 1530is capable of storing information related to a second access node whichperforms wireless communication using a second wireless accesstechnology. The storage unit 1530 provides the stored data according tothe request of the controller 1540.

The controller 1540 controls all the operations of the UE. For example,the controller 1540 controls the baseband processing unit 1520 and theRF processing unit 1510 to perform the transmission/reception ofsignals. The controller 1540 controls the storage unit 1540 tostore/read data therein/therefrom. To this end, the controller 1540 iscapable of including at least one processor. For example, the controller1540 is capable of including a communication processor (CP) forcontrolling the communication and an application processor (AP) forcontrolling higher layers such as applications. According to variousembodiments of the present invention, the controller 1540 is capable ofcontrolling the UE to perform the functions and the procedures describedabove referring to FIGS. 9 to 14 .

FIG. 16 is a block diagram showing an ENB included in a wirelesscommunication system according to Embodiment 2 of the present invention.

As shown in FIG. 16 , the ENB includes an RF processing unit 1610, abaseband processing unit 1620, a backhaul communication unit 1630, astorage unit 1640, and a controller 1650.

The RF processing unit 1610 performs functions related to thetransmission/reception of signals via a wireless channel, e.g., theconversion of frequency band, the amplification, etc. The RF processingunit 1610 up-converts baseband signals output from the basebandprocessing unit 1620 into RF band signals and transmits the RF signalsvia an antenna. The RF processing unit 1610 down-converts RF bandsignals received via the antenna into baseband signals. The RFprocessing unit 1610 is capable of including a transmission filter, areception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC,etc. Although the embodiment is shown in FIG. 16 so that the RFprocessing unit 1610 includes only one antenna, it should be understoodthat the RF processing unit 1610 may be modified to include a number ofantennas. The RF processing unit 1610 may also be implemented to includea number of RF chains. The RF processing unit 1610 is capable ofperforming a beamforming operation. In order to perform a beamformingfunction, the RF processing unit 1610 is capable of adjusting the phaseand amplitude of individual signals transmitted/received via a number ofantennas or antenna elements. The RF processing unit 1610 is capable oftransmitting one or more layers, thereby performing the downlink MIMOfunction.

The baseband processing unit 1620 performs the conversion betweenbaseband signals and bitstream according to a physical layerspecification (rule) of a first wireless access technology. For example,in the data transmission, the baseband processing unit 1620 encodes andmodulates a transmission bitstream, thereby creating complex symbols. Inthe data reception, the baseband processing unit 1620 demodulates anddecodes baseband signals output from the RF processing unit 1610,thereby restoring a reception bitstream. For example, in the datatransmission according to the orthogonal frequency division multiplexing(OFDM), the baseband processing unit 1620 encodes and modulates atransmission bitstream to create complex symbols, maps the complexsymbols to sub-carriers, and configures OFDM symbols through the inversefast Fourier transform (IFFT) operation and the cyclic prefix (CP)insertion. In the data reception, the baseband processing unit 1620splits baseband signals output from the RF processing unit 1610 intoOFDM symbol units, restores signals mapped to sub-carriers through thefast Fourier transform (FFT) operation, and then restores a receptionbitstream through the demodulation and decoding operation. The basebandprocessing unit 1620 and the RF processing unit 1610 perform thetransmission and reception of signals as described above. Therefore, thebaseband processing unit 1620 and the RF processing unit 1610 may alsobe called a transmitter, a receiver, a transceiver, a communicationunit, a wireless communication unit, etc.

The backhaul communication unit 1630 provides interfaces to communicatewith other nodes in the network. That is, the backhaul communicationunit 1630 converts: a bitstream into a physical signal to be transmittedto other nodes of the primary ENB, e.g., an auxiliary ENB, a corenetwork, etc.; and a physical signal from the other nodes into abitstream.

The storage unit 1640 stores a default program for operating the primaryENB, applications, settings, data, etc. In particular, the storage unit1640 is capable of storing information regarding a bearer allocated tothe connected UE, a measurement result reported from the connected UE,etc. The storage unit 1640 is capable of providing the dual connectivityfunction to UE or storing reference information to determine whether theENB terminates the dual connectivity operation. The storage unit 1640provides the stored data according to the request of the controller1650.

The controller 1650 controls all the operations of the primary ENB. Forexample, the controller 1650 controls the baseband processing unit 1620,the RF processing unit 1610 and the backhaul communication unit 1630 toperform the transmission/reception of signals. The controller 1650controls the storage unit 1640 to store/read data therein/therefrom. Tothis end, the controller 1650 is capable of including at least oneprocessor. The controller 1650 is capable of including a dualconnectivity controller 1652 which provides UEwith a dual connectivityfunction. For example, the controller 1650 is capable of controlling theprimary ENB to perform the functions and procedure described abovereferring to FIGS. 9, 11 and 13 .

Embodiment 3

The present invention relates to a method and apparatus for performingScheduling Request (SR) in a plurality cells with PUCCH in an LTE mobilecommunication system.

FIG. 7 is a diagram illustrating LTE system architecture to which thepresent invention is applied.

Referring to FIG. 7 , a radio access network of an LTE system includesevolved Node Bs (eNBs) 705, 710, 715, and 720, a Mobility ManagementEntity (MME) 725, and a Serving-Gateway (S-GW) 730. A User Equipment(hereinafter, referred to as UE or terminal) 735 connects to an externalnetwork via the eNBs 705, 710, 715, and 720 and the S-GW 730.

In FIG. 7 , the eNBs 705, 710, 715, and 720 correspond to legacy node Bsof a Universal Mobile Telecommunications System (UMTS). The eNBs 705,710, 715, and 720 allow the UE 735 to establish a radio channel and areresponsible for functions more complicated as compared to the legacynode B. In the LTE system, since all the user traffic services includingreal time services such as Voice over Internet Protocol (VoIP) areprovided through a shared channel, there is a need of a device toschedule data based on the state information (such as buffer status,power headroom status, and channel condition of the UE), and the eNBs705, 710, 715, and 720 are responsible for such functions. Typically,one eNB controls a plurality of cells. In order to secure a data rate ofup to 100Mbps, the LTE system adopts Orthogonal Frequency DivisionMultiplexing (OFDM) as a radio access technology in up to 20 MHzbandwidth. Also, the LTE system adopts Adaptive Modulation and Coding(AMC) to determine the modulation scheme and channel coding rate inadaptation to the channel condition of the UE. The S-GW 730 is an entityto provide data bearers so as to establish and release data bearersunder the control of the MME 725. The MME 725 is responsible formobility management of UEs and various control functions and may beconnected to a plurality of eNBs.

FIG. 8 is a diagram illustrating a radio protocol stack of an UE systemto which the present invention is applied. The LTE radio protocol stackfor the UE and eNB consists of Packet Data Convergence Protocol (PDCP)805 (1840), Radio Link Control (RLC) 810 (835), Medium Access Control(MAC) 815 (830), and Physical (PHY) 820 (825). The PDCP 805 (840) isresponsible for IP header compression/decompression, and the RLC 810(835) is responsible for segmenting the PDCP Protocol Data Unit (PDU)into segments suitable in size for Automatic Repeat Request (ARQ)operation. The MAC 815 (830) is responsible for establishing connectionsto a plurality of RLC entities to multiplex the RLC PDUs into MAC PDUsand demultiplex the MAC PDUs into RLC PDUs. The PHY 820 (825) performschannel coding on the MAC PDU and modulates the MAC PDU into OFDMsymbols to transmit over radio channel or performs demodulation andchannel-decoding on the received OFDM symbols and delivers the decodeddata to the higher layers.

FIG. 17 is a diagram for explaining the enhanced carrier aggregation ofa UE. Referring to FIG. 17 , an eNB transmit/receive signals over aplurality of carriers in several frequency bands. For example, when theeNB 1905 transmits the signals over the uplink carriers of four cells, aterminal transmits/receives data through one of the cells in the legacysystem. However, a UE having the carrier aggregation capability cantransmit/receive data over several carriers simultaneously. The eNB 1905may allocate more carriers to the UE 1930 having the carrier aggregationcapability depending on the situation. If it is assumed that a cell isformed by one downlink carrier and one uplink carrier of an eNB in theconventional concept, the carrier aggregation may be understood as a UEtransmits/receives data through multiple cells simultaneously. In thiscase, the peak data rate increases in proportion to the number ofaggregated carriers. The LTE Rel-10 carrier aggregation technique iscapable of configuring up to 5 cells to one UE. One of the configuredcells has to have PUCCH inevitably and this cell is referred PrimaryCell (PCell) 1910 while the rest cells having no PUCCH are referred toas Secondary Cell (SCell) 1915, 1925. The PCell is characterized by thefunctions of a legacy serving cell such as handover and RLF proceduresas well as by PUCCH. In the following description, if the UE receivesdata over a certain downlink carrier and transmits data over a certainuplink carrier, this means that the UE transmits/receives data using thecontrol and data channels provided in the cell corresponding to a centerfrequency and frequency band defining the carrier. Although theembodiments of the present invention are to a LTE system for explanationconvenience, the present invention can be applied to various wirelesscommunication systems supporting the carrier aggregation. In the Rel-10carrier aggregation technology, only the PCell can have PUCCH. However,if the information amount to be transmitted to the eNB increases, it maybe burdensome to process the corresponding information with a singlePUCCH. Particularly in LTE Rel-13, discussion on the idea for supportingup to 32 carriers is underway, and if it is possible to configure PUCCHto a SCell as well as the PCell, this is advantageous in terms of PUCCHload distribution. There is therefore a proposal of introducing PUCCH tothe SCell as well as the PCell. In the embodiment of FIG. 17 , a PUCCHSCell 1920 is introduced additionally. In the present invention, theSCell having PUCCH is referred to as PUCCH SCell. In the legacy system,all PUCCH-related signals are transmitted to the eNB through the PCell.However, in the case that a plurality of PUCCHs exist, it is necessaryto determine the PUCCH for transmitting SCell-specific PUCCH signals tothe eNB. Since there are a plurality of PUCCHs, it is necessary toselect a PUCCH for transmitting the SCell-specific PUCCH signals to theeNB. Assuming two PUCCHs as shown in FIG. 17 , the cells may be sortedinto a group of cells using the PUCCH of the PCell 1910 and a group ofcells using the PUCCH of a certain SCell 1920. In the present invention,the groups are referred to as PUCCH cell groups.

FIG. 18 is a diagram for explaining PUCCH SCell activation in accordancewith the normal SCell activation procedure. A UE receives an RRC messageindicative of adding a PUCCH SCell from an eNB as denoted by referencenumber 2000. At this time, the UE configures the PUCCH SCell. When theUE has completed configuration of the PUCCH SCell, the PUCCH SCell is ina deactivated state as denoted by reference number 2005. Afterward, ifan Activation/Deactivation MAC CE is received from the eNB, the UEactivates the PUCCH SCell as denoted by reference number 2010. At thistime, the eNB may not transmit the Activation/Deactivation MAC CE to theUE right before completing the configuration. This is because the eNBdoes know the accurate time when the UE completes preparation forreceiving the Activation/Deactivation MAC CE. By taking notice of this,the eNB is likely to transmit the Activation/Deactivation MAC CE to theUE after some marginal time. If the PUCCH SCell activation is completed,the UE reports a valid CSI for the SCell and transmits SRS as denoted byreference number 2015. Even after the activation has completed, the eNBdoes not know the accurate time when the UE starts transmitting the CSIreport and SRS. Thus the eNB has to perform blind decoding until theabove information are received. This increases the complexity of theeNB. If uplink synchronization is not achieved, the eNB transmits aPDCCH order to the UE to perform random access. In this case, thelatency increases before the CSI report and SRS transmission.

FIG. 19 shows a legacy Activation/Deactivation MAC Control Element (A/DMAC CE) format. The A/D MAC CE has a fixed length and consists of sevenCi fields 2100 and one Reserved (R) field 2105. The eNB transmits theA/D MAC CE to activate or deactivate the configured SCells. Each Cifield corresponds to the SCell indicated by SCellIndex i. Each Ci filedis set to 1 for activation of the corresponding SCell or to 0 fordeactivation of the corresponding SCell.

FIG. 20 is a diagram illustrating an extended A/D MAC CE for supportingup to 32 serving cells. Since the legacy A/D MAC CE format has 7 Cifields, it is possible to support up to 7 serving cells. If the numberof serving cells increases up to 32, the legacy A/D MAC CE cannotindicate all the states of the serving cells. Thus, a new A/D MAC CE isdefined to have the size of 4 bytes. Since the PCell is always in theactivated state, it is ruled out in the A/D MAC CE. Accordingly, it isenough to indicate the activated/deactivated states of total 31 servingcells. Depending on the position of the R bit, A/D MAC CE format varies.Parts (a) and (b) of FIG. 20 show examples of the extended A/D MAC CE.If the first byte is designed to be identical with the legacy A/D MACCE, the extended A/D MAC CE is formed as shown in part (a) of FIG. 20 .Otherwise, if the R bit is arranged in the last byte, the extended A/DMAC CE is formed as shown in part (b) (605) of FIG. 20 . In the presentinvention, the description is made based on part (a) (600) of FIG. 20 .Each Ci field corresponds to a SCell. Each Ci field also corresponds tothe SCell indicated by the SCellIndex i.

The extended A/D MAC CE is 4 times longer than the legacy A/D MAC CE soas to make it possible for the UE to have a capability of supporting upto 32 serving cells, but it is not preferred to always use the extendedA/D MAC CE from the viewpoint of signaling overhead. Thus the presentinvention is characterized by determining whether to use the extendedA/D MAC CE depending on the number of configured SCells. The SCells maybe sorted into several types. Examples of the SCell types include anormal SCell, a PUCCH SCell capable of transmitting PUCCH, an LAA SCellusing an unlicensed frequency band (ISM band), and Wi-Fi SCell used inthe LTE-Wi-Fi integration technology. In the present invention, it isassumed that the activation/deactivation operation is not applied to theWi-Fi SCell.

FIG. 21 is a signal flow diagram illustrating a method of selecting oneof the legacy and extended A/D MAC CEs according to the presentinvention. A UE 2300 camps on a serving cell at step 2310. The UEperforms an RRC Connection Establishment procedure with an eNB 2305 fordata communication at step 2315. The eNB requests UE capabilityinformation at step 2320. The UE sends the eNB its capabilityinformation at step 2325. The capability information includes theinformation on whether it is possible to support up to 32 serving cellswhich is more than 5 serving cells as in the legacy system. Thecapability information may also include the information on whether LLAand LTE-Wi-Fi integration are supported. If the UE capabilityinformation is acquired, the eNB reconfigures the UE based on thisinformation at step 2330. The reconfiguration information may includethe information related to the configuration of normal SCell, PUCCHSCell, LLA SCell, and Wi-Fi SCell. If the RRC Connection Reconfigurationmessage including the configuration information is received, the UEchecks the information related to the configurations of various SCells.If the message includes the configuration information of those SCells,the UE configures the normal SCell, PUCCH SCell and LLA SCell andregards that the configured SCells are in the deactivated state. In thecase of the Wi-Fi SCell, however, if an association/authenticationprocedure is completed and then the UE regards that the SCell is in theactivated state. The eNB determines an A/D MAC CE formation for use inactivating or deactivating at least one SCell according to predeterminedrules at step 2335. These rules include:

First rule: If the number of SCells, with the exception of the Wi-FiSCell, is equal to or less than 7, then the legacy A/D MAC CE format isused. Otherwise, if the number of SCells is greater than 7, the extendedA/D MAC CE format is used.

Second rule: If the highest value of the SCellIndex of the SCells, withthe exception of the Wi-Fi SCell, is equal to or less than 7, the legacyA/D MAC CE format is used. Otherwise, if the highest value is greaterthan 7, the extended A/D MAC CE format is used, and at least one of thetwo rules is applied.

The two A/D MAC CE formats may use the same LCID or different LCIDs. Inthe case of using the same LCID, the UE may check the type of the A/DMAC CE formation to be received in advance based on the number of SCellsconfigured to itself and the types of the SCells. In the case of usingdifferent LCIDs, the UE may check whether the legacy A/D MAC CE or theextended A/D MAC CE is used based on the LCID explicitly. Using theserules, the eNB selects one of the A/D MAC CE formats and sends the UEthe A/D MAC CE in the selected format at step 2340 or 2345.

FIG. 22 is a flowchart illustrating an eNB operation according to thepresent invention. The eNB performs an RRC Connection Establishmentprocedure with a UE for data communication at step 2400. The eNBreceives UE capability information from the UE at step 2405. The eNBsends the UE an RRC Connection Reconfiguration message forreconfiguration at step 2410. The RRC message may include informationnecessary for configuring a plurality of SCells. The configurationinformation may include information related to configuration of normalSCell, PUCCH SCell, LAA SCell, and Wi-Fi SCell. The eNB triggersactivation or deactivation of at least one of the SCells configured tothe UE at step 2415. The eNB determines whether to use the legacy A/DMAC CE or the extended A/D MAC CE according to predetermined rules atstep 2420. For example, if the highest value of the SCellIndex of theSCells, with the exception of the Wi-Fi SCell, is equal to or less than7, the eNB determines to use the legacy A/D MAC CE format at step 2425.Otherwise, if the highest value is greater than 7, the eNB determines touse the extended A/D MAC CE format at step 2430.

FIG. 23 is a flowchart illustrating a UE operation according to thepresent invention. A UE camps on a serving cell at step 2500. The UEperforms an RRC Connection Establishment procedure with an eNB for datacommunication at step 2505. The UE sends UE capability information tothe eNB at step 2510. The UE receives an RRC Connection Reconfigurationmessage from the eNB at step 2515. The RRC message may include theinformation necessary for configuring a plurality of SCells to the UE.The configuration information includes information related to theconfiguration of normal SCell, PUCCH SCell, LAA SCell, and Wi-Fi SCell.The UE checks the received configuration information to configure thenormal SCell, PUCCH SCell, and LLA SCell and then regards that the cellsare in the deactivated state at step 2520. In the case of the Wi-FiSCell, the UE assumes that the Wi-Fi SCell is in the activated stateafter the association/authentication has been completed. The UE receivesthe A/D MAC CE indicative of activation or deactivation of at least oneof the SCells configured to the UE and determines whether the A/D MAC CEis the legacy MAC CE or the extended MAC CE at step 2525. If the legacyA/D MAC CE is received, the UE keeps the current states (activated ordeactivated) for the SCells corresponding to the SCellIndex valuesgreater than 7 at step 2530. The UE ignores the Ci fields correspondingto the Wi-Fi SCells among the SCells corresponding to the SCellIndexvalues in the range between 1 and 7 and keeps the current state for theWi-Fi SCells at step 2535. The UE activates or deactivates the normalSCells, PUCCH SCells, and LAA SCells corresponding to the ScellIndexvalues in the range between 1 and 7 according to the corresponding Cifields. If the extended A/D MAC CE is received, the UE ignores the Cifields corresponding to the Wi-Fi SCells and keeps the current statethereof at step 2545. The UE activates or deactivates the normal SCells,PUCCH SCells, and LAA SCells according to the values of Ci fieldscorresponding thereto at step 2550.

FIG. 24 is a block diagram illustrating a UE according to the presentinvention. The UE transmits and receives data to and from a higher layer2605, transmits and receives controls messages through a control messageprocessing unit 2607, multiplexes, in a transmission mode, the data bymeans of a multiplexing device 2603 and transmits the multiplexed databy means of the transceiver 2601 under the control of a control unit2609, receives, in a reception mode, a physical signal by means ofreceiver under the control of the control unit 2609, demultiplexes thereceived signal by means of a demultiplexing unit 2603, and delivers thedemultiplexed signal to the higher layer 2605 or the control messageprocessing unit.

In the present invention, if an A/D MAC CE is received, the controlmessage processing unit 2607 notifies the SCell activation/deactivationprocessing unit 2611 to determine the first timing in the activatedstate and, when the first timing arrives, to command the control unit2609 and the control message processing unit 2607 to perform thesupposed operations. If it is commanded to deactivate an activatedSCell, the SCell activation/deactivation processing unit 2611 determinesa second timing and notifies the control unit 2609 and the controlmessage processing unit 2607 of first operations to be performed beforethe arrival of the second timing and commands and of second operationsto be performed at the second timing.

The proposed method is capable of performing predetermined operations atpredetermined timings in association with SCell activation anddeactivation in the case of using the carrier aggregation technique soas to make it possible to protect against malfunction and to performaccurate operations.

According to various embodiments of the present invention, the methodand apparatus is capable of performing the measurement using radioaccess technologies (RATs) that differ from each other in a wirelesscommunication system, and also capable of guaranteeing compatibilitywith versions of RATs which will be developed. The methods according toembodiments described in the claims or description can be implementedwith hardware, software, and a combination thereof. When the methods areimplemented with software, a computer-readable storage media where oneor more programs (software modules) are stored is provided. One or moreprograms stored in the computer-readable storage media are configuredfor execution by one or more processors in the electronic devices. Oneor more programs include instructions for enabling the electronic deviceto execute the methods according to embodiments described in the claimsor in the description. These programs (software modules and software)are stored in: Random Access Memory (RAM), flash memory, non-volatilememory, Read Only Memory (ROM), Electrically Erasable Programmable ReadOnly Memory (EEPROM), magnetic disc storage device, Compact Disc-ROM(CD-ROM), Digital Versatile Discs (DVDs) or other types of opticalstorage device, magnetic cassette, etc. or a combination thereof. Inaddition, two or more of the same type of memories form a memory block.In addition, the programs may also be stored in an attachable storagedevice accessible through a communication network, such as Internet,Intranet, Local Area Network (LAN), Wide Area Network (WAN), StorageArea Network (SAN) or a combination thereof. This storage device may beconnected to the apparatus according to the present invention viaexternal ports. In addition, a separate storage device of acommunication network may be connected to the apparatus according to thepresent invention.

The terms as used in various embodiments of the present invention aremerely for the purpose of describing particular embodiments and are notintended to limit the present disclosure. Singular forms are intended toinclude plural forms unless the context clearly indicates otherwise.

Although embodiments of the invention have been described in detailhereinabove, it should be understood that many variations andmodifications of the basic inventive concept herein described, which maybe apparent to those skilled in the art, will still fall within thespirit and scope of the embodiments of the invention as defined in theappended claims.

What is claimed is:
 1. A method performed by a terminal in a wirelesscommunication system, the method comprising: receiving, from a basestation, a radio resource control (RRC) reconfiguration messageconfiguring a medium access control (MAC) parameter for the terminal;identifying an uplink grant for a MAC protocol data unit (PDU);identifying that skip uplink transmission information indicating for theterminal to skip an uplink transmission is configured in the RRCreconfiguration message and that the uplink grant is addressed to acell-radio network temporary identifier (C-RNTI) or is a configureduplink grant; and skipping a generation of the MAC PDU for the uplinkgrant, in case that a MAC service data unit (SDU) for the MAC PDU doesnot exist, and the MAC PDU includes only a padding buffer status report(BSR).
 2. The method of claim 1, further comprising generating the MACPDU for the uplink grant, in case that the skip uplink transmissioninformation is not configured in the RRC reconfiguration message and theuplink grant is addressed to the C-RNTI.
 3. The method of claim 1,wherein the skip uplink transmission information includes 1 bit toindicate for the terminal to skip the uplink transmission.
 4. The methodof claim 1, further comprising generating the MAC PDU for the uplinkgrant, in case that the MAC SDU for the MAC PDU exists.
 5. A methodperformed by a base station in a wireless communication system, themethod comprising: transmitting, to a terminal, a radio resource control(RRC) reconfiguration message configuring a medium access control (MAC)parameter for the terminal; and allocating an uplink grant for a MACprotocol data unit (PDU), wherein a generation of the MAC PDU is skippedfor the uplink grant, in case that: skip uplink transmission informationindicating for the terminal to skip an uplink transmission is configuredin the RRC reconfiguration message and the uplink grant is addressed toa cell-radio network temporary identifier (C-RNTI) or is a configureduplink grant, and a MAC service data unit (SDU) for the MAC PDU does notexist, and the MAC PDU includes only a padding buffer status report(BSR).
 6. The method of claim 5, wherein the MAC PDU is generated forthe uplink grant, in case that the skip uplink transmission informationis not configured in the RRC reconfiguration message and the uplinkgrant is addressed to the C-RNTI.
 7. The method of claim 5, wherein theskip uplink transmission information includes 1 bit to indicate for theterminal to skip the uplink transmission.
 8. The method of claim 5,wherein the MAC PDU is generated for the uplink grant, in case that theMAC SDU for the MAC PDU exists.
 9. A terminal in a wirelesscommunication system, the terminal comprising: a transceiver; and acontroller configured to: receive, from a base station, a radio resourcecontrol (RRC) reconfiguration message configuring a medium accesscontrol (MAC) parameter for the terminal, identify an uplink grant for aMAC protocol data unit (PDU), identify that skip uplink transmissioninformation indicating for the terminal to skip an uplink transmissionis configured in the RRC reconfiguration message and that the uplinkgrant is addressed to a cell-radio network temporary identifier (C-RNTI)or is a configured uplink grant, and skip a generation of the MAC PDUfor the uplink grant, in case that a MAC service data unit (SDU) for theMAC PDU does not exist, and the MAC PDU includes only a padding bufferstatus report (BSR).
 10. The terminal of claim 9, wherein the controlleris further configured to generate the MAC PDU for the uplink grant, incase that the skip uplink transmission information is not configured inthe RRC reconfiguration message and the uplink grant is addressed to theC-RNTI.
 11. The terminal of claim 9, wherein the skip uplinktransmission information includes 1 bit to indicate for the terminal toskip the uplink transmission.
 12. The terminal of claim 9, wherein thecontroller is further configured to generate the MAC PDU for the uplinkgrant, in case that the MAC SDU for the MAC PDU exists.
 13. A basestation in a wireless communication system, the base station comprising:a transceiver; and a controller configured to: transmit, to a terminal,a radio resource control (RRC) reconfiguration message configuring amedium access control (MAC) parameter for the terminal, and allocate anuplink grant for a MAC protocol data unit (PDU), wherein a generation ofthe MAC PDU is skipped for the uplink grant, in case that: skip uplinktransmission information indicating for the terminal to skip an uplinktransmission is configured in the RRC reconfiguration message and theuplink grant is addressed to a cell-radio network temporary identifier(C-RNTI) or is a configured uplink grant, and a MAC service data unit(SDU) for the MAC PDU does not exist, and the MAC PDU includes only apadding buffer status report (BSR).
 14. The base station of claim 13,wherein the MAC PDU is generated for the uplink grant, in case that theskip uplink transmission information is not configured in the RRCreconfiguration message and the uplink grant is addressed to the C-RNTI.15. The base station of claim 13, wherein the skip uplink transmissioninformation includes 1 bit to indicate for the terminal to skip theuplink transmission.
 16. The base station of claim 13, wherein the MACPDU is generated for the uplink grant, in case that the MAC SDU for theMAC PDU exists.